nordic road and transport research 3-2000
DESCRIPTION
A joint publication with the latest research findings of six public research organisations in Denmark, Finland, Iceland, Norway and Sweden.TRANSCRIPT
No 3 · 2000 News from Denmark, F inland, Iceland, Norway and Sweden
International co-operation projects:EU – Pollution in soil and groundwater along roads p. 4Russia – Harmonisation of road standards p.20Ghana – Driver training programme p.22
Danish Road Directorate (DRD)The Road Directorate, which is a part of The Ministry of Trans-
port, Denmark, is responsible for development and management
of the national highways and for servicing and facilitating traffic
on the network. As part of this responsibility, the Directorate
conducts R&D, the aim of which is to contribute to efficient road
management and to the safe use of the network. The materials
research component is carried out by the Danish Road Institute
while other R&D activities – primarily safety and environmen-
tal research – are carried out by the Directorate’s operational
departments.
Technical Research Centre of Finland(VTT), Communities and InfrastructureCommunities and Infrastructure, employing a staff of 175, is one
of the nine Operating Units of the Technical Research Centre of
Finland (VTT), which has a total staff of 3,000. Research at this
Operating Unit covers all aspects of transport, road engineering,
geotechnology and urban planning. The unit has active inter-
national relations and a prominent role in these research areas on
the national level.
Public Roads Administration (PRA),IcelandThe duty of PRA is to provide society with a road system
according to its needs and to offer service aiming at safe,
unobstructed traffic. The number of employees is about 340.
Applied research concerning road construction, maintenance and
traffic and safety is to some extent performed or directed by the
PRA. The authority with its Research and Development division
is responsible for road research in Iceland.
Norwegian Public RoadsAdministration (NPRA)The Norwegian Public Roads Administration is one of the
administrative agencies under the Ministry of Transport and
Communications in Norway. The NPRA is responsible for the
development and management of public roads and road
traffic, as well as the Vehicle Department. This responsibility
includes research and development of all areas related to road
transport, and the application of R&D products.
Institute of Transport Economics (TØI)The Institute of Transport Economics is the national institution
for transport research and development in Norway. The main
objectives of the Institute are to carry out applied research and
promote the application and use of results through consultative
assistance to public authorities, the transport industry and others.
The Institute is an independent research foundation employing
about one hundred persons.
The Swedish National Road andTransport Research Institute (VTI)is responsible for research and development in road construction,
maintenance, road traffic and transport, railroads, rail transport,
vehicles, road user behaviour, traffic safety and the environment.
The Institute is state-owned and has a total of 215 employees.
Volume 12 · No. 3 · December 2000
Editorial notesNordic Road & Transport Research is ajoint publication of six public road andtransport research organisations in theNordic countries, Denmark, Finland, Ice-land, Norway, and Sweden. The mainobjective of the publication is to dis-seminate research results and news fromthe institutions, especially to researchersand decision makers. Each institution isresponsible for the selection and presenta-tion of the material from its own scope ofactivities.
Nordic Road & Transport Research ispublished three times a year. It is regularlysent out, free of charge, to recipients se-lected by the five joint publishers. Freesample copies are also sent out on specialrequest.
Reproduction and quotation of the textare allowed if reference is made to theauthor and source. However, legislationregulates and restricts the right to repro-duce the illustrations. Please contact therespective publishing institution for infor-mation.
Advertising is not accepted.Correspondence about the contents of
the publication:Please write to the author or to the
respective publishing organisation.Requests for back issues, and notification
of address changes:Readers outside the Nordic countries:
please write to the Editor-in-chief at the VTIin Sweden.
Readers in the Nordic countries: pleasecontact the publishing institution of yourcountry.
Addresses: see back cover.
The Editorial Board consistsof the following representativesof the publishing institutions.
Editor-in-ChiefSigvard Tim, Swedish National Roadand Transport Research InstituteDenmarkHelen Hasz-Singh, Danish Road InstituteFinlandKari Mäkelä, Technical Research Centreof Finland, Communities and Infrastruc-tureIcelandHreinn Haraldsson, Public RoadsAdministrationNorwayHelge Holte, NorwegianPublic Roads AdministrationHarald Aas, Institute of TransportEconomics
Production: VTI InformationPlace of publication: Linköping, SwedenIssue: 3,500ISSN: 1101-5179
Cover Photo: Jonas Ekströmer, Pressens Bild
C O N T E N T S
Danish Road Directorate (DRD) ............................................................................................................. 24
Technical Research Centre of Finland (VTT), Communities and Infrastructure) ............... 25
Institute of Transport Economics (TØI) ................................................................................................ 26
Swedish National Road and Transport Research Institute (VTI) ............................................. 30
A N N O T A T E D R E P O R T S
Examination of pollution in soil and water along roads ...................... 4Danish Road Directorate (DRD)
Rutting and weathering characteristics of Danish asphalt pavements .. 7Danish Road Directorate (DRD)
Preventing the blistering of bridge deck waterproofing ..................... 10Technical Research Centre of Finland (VTT), Communities and Infrastructure
Promoting safe walking and cycling ................................................. 12Technical Research Centre of Finland (VTT), Communities and Infrastructure
Strengthening with carbon fibres ...................................................... 16Norwegian Public Roads Administration (NPRA)
VTI supports better roads in Russia ................................................... 20Swedish National Road and Transport Research Institute (VTI)
Driver training programme in Ghana ................................................ 22Swedish National Road and Transport Research Institute (VTI)
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20004
DANISH ROAD DIRECTORATE (DRD)
During recent years, more emphasis
has been put on the assessment of
the environmental impact caused by
roads and traffic, and especially on
the pollution of the soil and water
near roads. This article gives a
description of the method used and
some results and preliminary
conclusions from studies at two sites
in Denmark.
The Road Directorate in Denmark has
evaluated in its environmental strategy
from 1996 that there is a need to gain
more knowledge and therefore a number
of projects have been started in order to
throw light on the influence of roads on
the environment.
One of these projects called Environ-
mental Monitoring has examined the
amount of pollution at areas near a road
(water and soil) by establishing two en-
vironmental study sites along the motor-
way network in Denmark.
The Road Directorate is also participat-
ing in the EU-project “POLMIT - Pollu-
tion of Groundwater and Soil by Road and
Traffic Sources: dispersal mechanisms,
pathways and mitigation measures”, in
which seven countries participate.
Parameters/polluting compounds
Which polluting compounds can be found
in soil and water as a result of roads and
traffic? Previously, there was a great deal
of focus on the heavy metal lead, which
was added to petrol. However, lead has
not been added to petrol in Denmark since
1994. Brakes, rust, paint, wear of tyres
and exhaust gasses contribute to remains
of polyaromatic hydrocarbons (PAH) and
also some heavy metals in the environ-
ment. Maintenance of roads leads to
spread of de-icing salts during winter and
traffic itself rubs some of the asphalt lay-
ers off the road surface, which are spread
to the surrounding areas.
In the POLMIT project and from the
samples of the Danish environmental
field sites, it was decided to make analy-
ses of the substances shown in table 1:
Choice of locality
17 possible localities were inspected and
screened during the summer and autumn
of 1997.
Based on the data found during the
screening and the criteria established, it
was decided to choose the localities on
taken from both sides of the road.
Several methods of collecting run-off
from the road were discussed. At each
field site, the run-off was caught by a
gutter which was 1 meter in length and 15
cm in width; the gutter was placed along-
side the asphalt edge dug into the top layer
of the soil (figure 2). The gutter was sepa-
rated into 10 sections and the water from
each of these sections was collected into
Examination of pollution in soil andwater along roads
two motorways at Vejenbrod (Zealand)
and Rud (Jutland).
Instrumentation of field sites
At the Danish field sites, all samples were
taken on the eastern side of the road, since
the prevailing direction of the wind is from
the west. The only exception was collec-
tion of ground- water, where samples were
Metals Cd, Cu, Cr, Pb, Zn, Ca, K, Mg and NaAnions Cl– and SO4
–
Organic parameters PAH, NVOC and THCVarious Suspended substances
Table 1: Parameters which are determined in the the Danish field study sites.
a bottle with a volume of 25 litre. Repre-
sentative samples were taken from each
bottle, the samples were mixed and ana-
lysed every month.
At four different distances from the
road pavement, samples were collected,
including splash from the road and rain
precipitation in a total deposition sampler
(figure 3). The total deposition sampler
consists of four gutters which had an area
of 0.016 m2, where the total precipitation
(wet/dry) was led into a collection bottle
which was dug into the ground. The
equipment has been used successfully in
the Netherlands.
Furthermore, in two positions 3 and 6
meters from the edge of the road samples
of the soil solution at a depth of 35 cm was
taken with an equipment produced in
Denmark (Prenard). The equipment con-
sists of a porous cup situated above
ground level which sucks soil solution
with the aid of a mechanical water pump,
and in that way continuously takes sam-
ples of soil solution.
On both sides of the road, groundwater
pipes were installed to take samples of the
secondary groundwater which at the Dan-
ish sites was found two to three meters
below the surface.Figure 1: Placing of the two Danish environ-
mental field sites.
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 5
DANISH ROAD DIRECTORATE (DRD)
Figure 2: Run-off sampler Figure 3: Total deposition sampler
Apart from the equipment mentioned
above, a rain gauge was installed at each
field site. It was connected to a data log-
ger which registered rain continuously. For
the sake of comparison, data was also col-
lected from the nearest weather station of
the Danish Meteorological Institute.
Results
This article presents a summary of the Dan-
ish data. All the results from the Danish
study sites will be given in the final report
from the POLMIT project, where the re-
sults from the other countries also will be
available.
Run-offFor the samples of run-off, conductivity was
measured. Figure 4 shows a graphic pres-
entation of the conductivity as a function
of time. A considerable increase can be
noted for both field sites during the winter
period, which is due to the use of de-icing
salt in Denmark. The amount of de-icing
salt used at the sites was almost identical
during the winter 98/99. The responsible
authorities state that at Vejenbrod approx.
14 kg/m2 was spread and at Rud 12 kg/m2.
Table 2 shows some of the parameters from
the examination of run-off from Vejenbrod.
The results from Rud show the same ten-
dency, however the level of some of the
parameters is different.
Total deposition
When analysing the samples from the total
deposition samplers, a corresponding in-
crease in conductivity can be seen for sam-
plers situated three meters from the road in
the period where salting takes place. In gen-
eral, the concentrations are low; however,
the concentration of zinc is high at both
sites.
made further analyses of organic com-
pounds possible.
Soil solutionIn the samples sucked up from a depth of
0.35 m, a considerable difference can be
There was only little water in the sam-
pler at Rud and it was therefore only possi-
ble to make a few analyses of the organic
parameters. The concentrations found from
the analyses are very low. The greater
amounts of water collected at Vejenbrod
Figure 4: Conductivity of road run-off as a function of time
Zn, Pb, Cl-, Sum NVOC, THC,µg/l µg/l µg/l PAH, µg/l µg/l
µg/l
Jul 69 8 3 <0.22 10,000 4,900Aug 75 8 4 <0.22 11,000 4,700Sep 68 9 5 <0.22 7,100 5,000Oct 47 12 4 <0.21 7,000 3,900Nov 455 11 1.500 <0.36 12,000 5,500Dec 144 18 2.500 <0.84 34,000 12,000Jan 210 25 1.500 2.0 25,000 12,000Feb 330 46 3.700 3.6 49,000 19,000Mar 170 21 1.200 2.5 30,000 8,400Apr 75 13 210 <0.42 21,000 1,100Maj 52 8 17 2.5 23,000 680Jun 180 29 5 2.0 31,000 1,200
Table 2: Summary of the analysis results from run-off, Vejenbrod.
25 000
20 000
15 000
10 000
5 000
0
Jul 98 Oct 98 Jan 99 Apr 99 Jul 99
Vejenbrod
Rud
Conductivity, run-off
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20006
DANISH ROAD DIRECTORATE (DRD)
Figure 5: Contents of chlorides in the groundwater
noted between the two sites as regards
conductivity. At Vejenbrod the sample
closest to the road (three meters from the
asphaltic edge) shows a considerable in-
crease during the winter, whereas the
samples six meters from the edge is reg-
istered with a constant level. The increase
in conductivity during the winter is not
nearly as pronounced at the site at Rud.
The concentration of chlorides is also
lower there than at Vejenbrod.
It applies for both sites that the concen-
tration of other parameters is low; how-
ever there is an increased content of To-
tal Hyd-ro Carbolic (THC) at Vejenbrod.
This can be explained by the fact that
there is a higher content of THC for the
total deposition.
Groundwater
The results of the analyses of the
groundwater from both sites show a
higher content of sodium and chloride in
the samples on the downstream side than
for the other side of the road. The down-
stream side was at both sites the eastern
side of the road. The values for chloride
are higher than for typical values found
in groundwater in Denmark. There were
no differences in the concentration of
chlorides from the two sites. Figure 5
shows the variation of chloride concen-
trations for the period.
At the site at Vejenbrod there is a high
content of THC in the first sample,
whereas there is a high content of heavy
metals at the site at Rud from the first
sample. This is not found again and may
be due to disturbances of the soil during
the installation of the pipes.
Soil samples
Soil samples were only taken once dur-
ing the project. The results represent an
accumulation throughout the period while
the roads have been trafficked; for
Vejenbrod 25 years, for Rud 4 years.
The level in the soil samples from Rud
is within the interval which can be ex-
pected in normal undisturbed Danish soil,
whereas it is quite clear that the concen-
trations in the soil samples from
Vejenbrod are very high. This difference
can be explained by the fact that the study
site at Vejenbrod has been exposed to in-
fluence from traffic for 25 years whereas
the motorway in Rud was opened four
years ago.
Conclusion and discussion
As expected, the analyses of inorganic pa-
rameters show that there are high concen-
trations of sodium and chloride in the run-
off and soil solution close to the road (3
meters) during the winter, when de-icing
salts are used.
The presence of chloride can cause a
washing of heavy metals from the soil,
since the chloride ions can form com-
plexes with heavy metals. It is however,
not possible to document this effect, since
the concentrations of heavy metals found
in the soil solution and groundwater sam-
ples is very low.
The analyses show that concentrations
of heavy metals in water samples from
soil solution and groundwater samples are
low, but it is seen that the zinc content in
the water samples from both stations ex-
ceed the requirement for drinking water
in Denmark. The concentrations of the
metals examined show a tendency that
they are higher during the winter.
The results of the soil samples at Rud
are on level with unpolluted soil samples
in Denmark. There is no influence from
the traffic or the road. The analysis results
for soil samples at Vejenbrod, after 25
years of accumulation of low soluble
compounds show much higher values -
the closer to the road, the higher the val-
ues.
By choosing two field sites with differ-
ent ages, as was the case, it is confirmed
that there is an increased concentration of
heavy metals and organic matter (PAH,
NVOH and THC) as a function of the to-
tal traffic volume. Various initiatives,
such as use of unleaded petrol and the re-
quirement of catalyst in new vehicles,
have had a positive effect in the wish to
reduce pollution.
In a way it can be seen that the great-
est influence of the soil and water from the
road and traffic is due to de-icing salt in
winter.
The results of the study sites show that
spreading of pollution from traffic and
roads is on a low level. On the other hand,
an accumulation of contaminating com-
pounds near the roads and also a spread
of pollution near the roads can be found
to such an extent, that mitigation must be
considered. Continuation of measure-
ments must be considered.
This article is a summary of a lecture
given at the 24th International Road Con-
ference of the Baltic Road Council in Au-
gust 2000. The entire proceedings have
been published on a CD-ROM.
Article specielly written by Knud A. Pihl
([email protected]) and Jørn Raaberg ([email protected])
for Nordic Road & Transport Research.
The content af chloride, groundwater
500
400
300
200
100
0
mg/1
Jul – Oct – Jan – Apr –Sep Dec Mar Jun
Vejenbrod upstream
VejenbroddownstreamRud upstream
Rud downstream
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 7
DANISH ROAD DIRECTORATE (DRD)
A three-year research project was
commenced in 1998 at the Danish
Road Institute to establish a basis
for evaluating the rutting and
weathering resistance of Danish
asphalt pavements. Some results
were presented in two papers at the
Euraspalt & Eurobitumen Congress
in Barcelona in September 2000.
The abstracts of the two papers and
a brief discussion of the results are
given below.
ABSTRACT 1:
Examination of Rutting and Weather-
ing Characteristics of various Danish
Road Classes
The Danish road network is divided
into four classes: Motorways, main
roads, rural roads and local roads. In or-
der to optimise the lifetimes of the bitu-
minous surfacing in these road classes
economically, it is necessary to consider
the rutting and weathering resistance of
road pavements. Optimisation of rutting
resistance often results in a lean, stone
rich layer that is less weather resistant
than a bitumen rich layer. For low traf-
ficked roads it is therefore important to
optimise weathering resistance, whereas
for heavily trafficked roads, optimising
rutting resistance is more important.
Ten pavements were selected that
were due for overlaying and which suf-
fered from rutting generated mainly in
the bituminous layers. Cores were taken
from these pavements in and between the
wheel tracks. On the basis of their rut-
ting and weathering resistance a number
of laboratory tests were conducted to
determine whether these different bitu-
minous materials could be classified as
suitable surfacing materials for three
road classes. These laboratory tests in-
cluded material composition, stripping
and dynamic creep test on the samples
from the upper 10 to 18 cm of the sur-
facing in the selected pavements.
The ten road sections have been classified
according to their rutting properties based
on creep rate determined by dynamic creep
tests and their stripping properties based
on the voids filled with bitumen. It is dem-
onstrated that the resistance to stripping
and resistance to permanent deformation
of the asphalt materials were not always
optimised in relation to traffic load. By
performing a few simple tests of the in situ
asphalt materials, a more economically
viable solution can be ensured.
Classification of roadsTen road sections were selected, based
on the following road classes:
• 2 motorways (M):
ADT > 20,000 and EASELs >1,400.
• 7 main roads (MR):
6,000 < ADT < 12,000 and 300 <
EASELs < 1,300.
• 1 rural road (RR):
ADT < 4,000 and EASELs < 300.
Dynamic creep tests were performed ac-
cording to FAS method 468-97. It was de-
cided to perform dynamic creep tests of
the entire pavement construction of the
three to four upper asphalt layers corre-
sponding to a layer thickness of 10-18 cm.
Based on the results of the dynamic creep
tests, the road sections have been classi-
fied according to their rutting properties:
• Good resistance to permanent defor-
mation: Creep rate ≤ 2.0 µe/pulse for
motorways and heavily trafficked
main roads.
• Medium resistance to permanent de-
formation: 2.0 µe/pulse < creep rate
≤ 4.0 µe/pulse for main roads.
• Poor resistance to permanent defor-
mation: Creep rate > 4.0 µe/pulse for
rural roads.
The weathering resistance test is per-
formed by determining the Stiffness
Modulus of the individual layer of the
pavement samples (cores with a diameter
of 100 mm) before and after the test sam-
ples have been exposed to an accelerated
weathering procedure. The Stiffness
Modulus was determined by the Notting-
ham Asphalt Tester (NAT) according to
British Standard DD 213:1993.
The pavement materials have been
classified with regard to their weather-
ing resistance according to the amount of
voids filled with bitumen, as follows:
Rutting and weathering characteris-tics of Danish asphalt pavements
Figure 1. Classifications with regard to permanent deformation (creep rate) and
weathering resistance (voids filled with bitumen) for ten Danish asphalt pavements.
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20008
• Good resistance to stripping: voids
filled with bitumen > 80%.
• Medium resistance to stripping:
60%< voids filled with bitumen <
80%.
• Poor resistance to stripping: voids
filled with bitumen < 60%.
Classifications with regard to permanent
deformation (creep rate) and weathering
resistance (voids filled with bitumen) is
correlated (Figure 1, see page 7). The ru-
ral road section 608 has good rutting re-
sistance, but poor durability, which is not
optimal seen from an economic point of
view in relation to the actual traffic load.
The motorway section 11 has only me-
dium rutting resistance despite the fact
that the actual traffic load is consider-
ably higher. The main road sections 125,
332A and 152/614 has poor rutting re-
sistance and the pavements are not eco-
nomically viable.
It should however be mentioned that
the tests described in the paper regard-
ing the rutting and stripping properties
are not suitable for mix design, where
laboratory samples usually are used. The
tests described are relevant when an ex-
isting road pavement is due for repairing.
The tests could improve the evaluation
whether it would be economically prof-
itable if one or several asphalt layers
should be removed before overlaying.
ABSTRACT 2:
Estimation of Permanent Deformation
in Danish Motorway Pavements
The maintenance of hot rolled asphalt
(HRA) motorway pavements in Den-
mark is either performed as an overlay
with a rut resistant wearing course or by
milling the HRA and paving with a rut
resistant binder course before overlay-
ing. To decide which alternative is the
better, the potential risk of flow rutting
in the existing pavement is tested in the
Danish Asphalt Rut Tester (DART).
The question is whether the HRA
layer should be removed, or the resist-
ance to permanent deformation is suffi-
cient. If there is insufficient resistance to
permanent deformation the material
should be renewed at least over that re-
gion where the maximum shear stresses
occur in the pavement.
This is normally 50-100 mm below
the surface. By applying a new 40 mm
wearing course, the HRA layer would en-
ter this zone of maximum shear stresses
and there would thereby be a potential
risk of flow rutting.
The objective of the research was to
estimate the potential risk of flow rutting
in three types of Danish HRA motorway
pavements. One was overlaid without re-
moving the HRA layer, one was overlaid
after removing the HRA layer and pav-
ing with a binder course in both lanes,
and one was overlaid after removing the
HRA layer and paving with a binder
course only in the heavy traffic lane.
The paper presents the results of the
accelerated testing of 12 slabs with all
bound layers cut from the motorway
pavements. An empirical model to esti-
mate rutting in the motorway pavement
is suggested. Based on accelerated test-
ing in DART and measurements of in-
field ruts, the rutting level after 15 years
of service life is estimated.
It is demonstrated that removing the
HRA allows the traffic and/or the
DANISH ROAD DIRECTORATE (DRD)
Figure 2. Cutting of slabs for wheel-tracking tests in DART from the motorway M40 Kolding.
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 9
DANISH ROAD DIRECTORATE (DRD)
number of hot days to increase signifi-
cantly without any risk of flow rutting.
It is only economically advantageous to
remove the HRA when such increases in
traffic are expected. The accelerated test-
ing in DART has to be performed for
each type of pavement as differences in
pavement condition and material compo-
sition may influence the rut resistance of
the pavement significantly.
Calibration of DART wheel-tracking results
The Danish Profilograph routinely meas-
ures ruts in all Danish motorway and
main road pavements. For three motor-
way pavements, the mean rut depth in
both wheel tracks over 2 kilometres is
calculated including the position where
the slabs tested in DART were cut (Ta-
ble 1 and Figure 2).
During the wheel-tracking test in
DART the correlation between rut depth
and the number of loads is monitored.
The rut depth is estimated by a power
function. For each measured in-field rut,
it is possible to calculate an equivalent
number of loads in DART using the
power model. The number of equivalent
loads is much smaller than the actual in-
field number of loads as test conditions
(temperature and speed) in DART accel-
erates the formation of ruts.
The flow rutting over 15 years, which
is the expected lifetime of the wearing
course, is estimated using the power
function and the estimated number of
equivalent loads in 15 years (Table 2).
The number of equivalent loads might
not be constant over all 15 years, due to
increases in traffic or the number of hot
days. The maximum acceptable rut depth
given in the Danish Road Standards is 15
mm. It is therefore acceptable to increase
the number of equivalent loads to cause
an estimated maximum rut depth of 15
mm.
The number of times that the esti-
mated number of equivalent loads is per-
mitted to increase is defined as the Maxi-
mum Increase Factor (MIF). For in-
stance, a factor of 10 means that the
number of equivalent loads may be as
much as ten times higher, while devel-
oping the permissible maximum rut
depth after 15 years.
MIF is of value, as the number of
equivalent loads is estimated from only
a few years of in-field observations and
the number of equivalent loads might in-
crease considerably. The accuracy of the
estimation is evaluated from MIF and the
Motorway Light Traffic Lane Heavy Traffic Lane
Maint.Rut COV MIF Maint.Rut COV MIFAlt.1) mm % Alt.1) mm %
M40 Knudshoved2) A 6.9 5 4 A 17.1 4 0.8M30 Koege B 4.0 10 128 B 5.1 16 51M40 Kolding A 7.8 6 4 B 6.4 16 8M40 Kolding B 4.1 17 24 A 13.0 12 1.4
1) Alternative A: Overlaying without removing the HRA layerAlternative B: Overlaying after removing the HRA layer and paving withbinder course
2) Slabs tested at three different temperatures
coefficient of variation (COV) of the es-
timated depth of rutting. The COV is the
ratio between the estimated standard de-
viation and the mean value from the test
results for three slabs.
It has been demonstrated that mainte-
nance alternative B allows the number of
equivalent loads to increase significantly
without any risk of flow rutting, consid-
ering the accuracy of the estimation. It
is not always economically advanta-
geous to use maintenance alternative B,
as in some cases the risk of rutting is suf-
ficiently reduced with the cheaper alter-
native A. The accelerated testing in
DART has to be performed for each spe-
cific pavement type and estimations have
to be based on calibrations with in-field
rut measurements.
Table 2. Estimated Flow Rutting over 15 Years and the Accuracy of Estimation
Motorway Overlay Rut measurementsLight Traffic Lane Heavy Traffic LaneDate Rut, mm Date Rut, mm
M40 Knudshoved 15-06-1997 06-10-1999 2.3 12-10-1998 4.1M30 Koege 07-10-1998 09-09-1999 1.9 09-09-1999 2.4M40 Kolding 11-05-1999 20-09-1999 1.4 20-09-1999 1.4
Table 1. In-field Rut Measurements with the Danish Profilograph
References
Proceedings of the papers submitted for
review, 2nd Eurasphalt & Eurobitume
Congress, 20-22 September, 2000, Bar-
celona – Spain, Book 1 sessions 1 & 4:
1. Jørn Raaberg ([email protected]) and
Jeanne Rosenberg ([email protected]): Exami-
nation of Rutting and Weathering Char-
acteristics of various Danish Road
Classes, pp.689-696.
1. Weathering Characteristics of vari-
ous Danish Road Classes, pp.689-696.
2. Carsten Bredahl Nielsen
([email protected]): Estimation of Perma-
nent Deformation in Danish Motor-
way Pavements, pp. 589-557.
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20001 0
TECHNICAL RESEARCH CENTRE OF FINLAND (VTT), COMMUNITIES AND INFRASTRUCTURE
Blistering is a delamination damage
of the bridge deck waterproofing
and it is caused by large fluctua-
tions of vapour pressure in the pore
spaces of the concrete layer under
the waterproofing. The blistering
research work included 15 separate
sub-studies, in which concrete and
waterproofing research were incor-
porated into the same project. The
project provided information about
the means to avoid the blistering
problem.
Blistering phenomena affecting bridge
deck waterproofing sheet membranes were
studied with the aim of clarifying the
causes of the blistering and generating
ways in which construction and repair
documents could be adjusted to remedy the
problem. The research project was funded
by the Bridge Unit of the Finnish National
Road Administration and it was carried out
in 1996-98 in collaboration with VTT
Communities and Infrastructure and VTT
Building Technology.
Blistering of waterproofings
Polymer-modified sheet membranes are
generally used as the waterproofing ma-
terial and polymer-modified cut-back
bitumen or epoxy as primers under the
sheet membranes in Finland.
The results of a site questionnaire
clearly revealed the timing of blistering es-
pecially for the years 1994-95. Most of the
blistered waterproofing membranes had
been laid at least one year before the blis-
tering was first observed. Blistering was
frequently observed in 1995 due to the pro-
motive weather conditions, but not one of
the waterproofing membranes laid in that
year exhibited any blistering. However,
many instances of blistering were observed
in the hot summer of 1997.
The maximum daily temperatures under
the membrane before the asphalting can
then be as high as 50oC, and the positive
gas pressure inside the air pockets remain-
ing beneath the membrane is of the order
of 0.03 MPa, which is sufficiently high to
raise the asphalt pavement if the membrane
is detached from the underlay. The relative
humidities in the surface layer of the slab
after waterproofing vary between 90 - 100
% in the first year.
Waterproofing site conditions
The waterproofing site condition require-
ments set out in Finnra’s instructions are
met on average on fewer than 20% of days
in the period April-October. Concentrat-
ing the works in the early summer is ad-
vantageous from the standpoint of work
quality. On the other hand, the brief work
season and the concentration of works in
a short period causes problems in the
scheduling and execution of waterproof-
ing works.
It can be concluded from a bridge deck
drying test carried out on site that hot sur-
facing equipment does not damage the
surface of the concrete underlay provided
that it is correctly used and heated with
sufficient caution. However weather pro-
tection or the timing of waterproofing
works at warm times of the year can be
considered better alternatives as far as the
quality of waterproofing work is con-
cerned.
Simulation of blistering in thelaboratory
A blistering simulator was designed and
built by VTT for the study, Figure 1.
Using this tool it was possible to experi-
mentally trace the formation mechanism
of the blisters and to clarify the factors
affecting blistering. The simulator was
used to examine 29 different waterproof-
ing systems.
The results of the simulator tests re-
vealed that the porosity of the concrete
affects the susceptibility of the sheet mem-
brane to blistering: a sheet membrane laid
on an air-entrained concrete underlay is
more susceptible to blistering than one laid
on non-air-entrained concrete. The use of
the epoxy sealant under the sheet mem-
brane was found to be the best way to pre-
vent blistering.
Preventing the blistering of bridgedeck waterproofing
Figure 1. VTT’s blistering simulator
PHOTO: TIMO UNHOLA
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 1 1
Quality of concrete and bitumen
An analysis of concrete samples taken
from the points where the sheet membrane
had blistered revealed that the total vol-
ume of air near the deck surface was large,
as much a 10% or more. The air content in
the surface layer of the deck was found to
be dangerously high as far as the risk of
blistering is concerned.
The bitumen tests showed that the prop-
erties of polymer-modified bitumen are
significantly weakened by overheating and
gave five factors that clearly contribute
towards the problem.
Conclusions
The following conclusions have been
made on the basis of the study:
• The volume of air in the fresh bridge
deck concrete may not exceed the air
volume requirement set on the basis
of frost resistance by more than three
percentage points and never by more
than 7%.
• Attention must be paid to the protec-
tive pore size distribution. The
number of voids should be as large as
possible.
• Sufficient and correctly timed
compaction of the surface layers
must be ensured, because improved
compaction reduces the volume of air
in the surface layer of the slab.
• Water spraying after final vibration
and finishing is recommended as the
curing method. The use of curing
material should be avoided.
• Design values should be set for the
roughness of the underlay surface.
• It is recommended that on bridge
sites the moisture in the concrete be
measured from cast-in-situ sensors
using a portable data logger.
• The most highly recommended wa-
terproofing method to prevent blister-
ing of the waterproofing membrane
with a high degree of certainty in
Finnish weather conditions is to use
epoxy sealant (figure 2) under the
membrane and to carry out the water-
proofing works under weather pro-
tection in accordance with the in-
structions for use of the epoxy mate-
rial, at the temperature permitted for
the use of polymer-modified bitu-
men, and using only materials ap-
proved for bridges.
• Waterproofing of a freshly placed
concrete surface is not recom-
mended. Because the weather condi-
tions required the use of weather
protection is recommended.
• The dew point temperature and the
temperature of the underlay should
always be measured and recorded
both before the commencement of
waterproofing work
• The bitumen melting kettle must be
equipped with a mixer and a thermo-
stat.
• The quality of the waterproofing
work must always be verified by
means of quality assurance tests.
Title:Prevention of bridge deck sheet
membrane waterproofing blistering.
Final report.
Author: Laukkanen Kyösti, Paroll Hem-
ming, Pitkänen Pertti, Vesikari Erkki
Series:Finnish National Road Adminis-
tration, Report 45/1998
Language:Finnish with English abstract
Figure 2. Applying of epoxy sealant
TECHNICAL RESEARCH CENTRE OF FINLAND (VTT), COMMUNITIES AND INFRASTRUCTURE
PHOTO: BESTSELLER OY
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20001 2
TECHNICAL RESEARCH CENTRE OF FINLAND (VTT), COMMUNITIES AND INFRASTRUCTURE
European experts suggest demo
projects as a key issue to promoting
safe walking and cycling. Another
highly ranked topic is implementing
a uniform comprehensive technique
for monitoring safe traffic behav-
iour among children, elderly and
disabled people around Europe.
A long-range Research & Development
(R&D) program for supporting long-range
national goals of safe mobility in road
transport is being developed on behalf of
the Finnish Ministry of Transport, the
Finnish Department of Motor Vehicles and
the Finnish Road Administration. The
work has been co-ordinated by VTT. The
program addresses the goals, necessary
R&D areas, and broad management proc-
ess for implementing R&D needs and gen-
erating new R&D ideas. As part of the
work, the Finnish Advisory Committee of
Traffic Safety has drafted a safety vision
as follows:
• The traffic environment must be
planned and designed so that nobody
dies or is severely injured in traffic.
• Research and development are to focus
on limiting fatalities in traffic by the
year 2025 to about 100 per year.”
Sale walking and cycling
The overall project includes 16 work pack-
ages, or major tasks. The results of the
work package presented in this paper deal
with promoting safe walking and cycling.
It has been the intent of the investigators
to cover all ‘important’ sub-areas, and to
identify experts for each of these.
The R&D ideas were first structured
into three sectors:
• Deeper understanding of necessary
changes
• Fuller quantification of the problems
and of progress made
• Safer bicycles and further crash protec-
tion.
Next, a total of 22 sub-areas were chosen
on the basis of recently published research
topics by the European Transport Safety
Council (Günther et al, 1999) and on re-
search ideas presented at a Finnish work-
shop on safe infrastructure with a sub-
theme dealing with promoting safe
walking and biking in urban areas.
Leading experts chosen
After the most important areas had been
identified, leading experts in those areas
were chosen. In some cases only one ex-
pert could be identified, in other cases
many were found (see Tables 1 – 3; col-
umn 3).
A questionnaire was sent to each of the
experts, giving them the opportunity to iden-
tify others in their area. Prioritising between
different areas was then done as ‘democrati-
cally’ as possible. A draft of this report was
sent to all participating experts and some
users of research (administrators and con-
sultants), and they were asked to ‘rank’ all
areas in order of importance to reach the
overall goal of promoting safe walking and
cycling. The result of the ranking is shown
in Tables 1 – 3; column 2.
Demo projects
The area ranked at the very top was
“How walking and cycling can form an
integral and attractive part of daily travel
by demo projects”. This deals with ways
of getting more people to walk and ride
bicycles on an everyday basis by provid-
ing better infrastructure such as a safe,
coherent, direct, comfortable and attractive
cycle network. Accompanying counter-
measures could be information and promo-
tion (by the city and/or corporations) to
encourage individual citizens or employ-
ees to walk or bike, and the creation of an
organisation to act as catalyst in the devel-
opment of pedestrian and bicycle friendly
planning. It is suggested to show best prac-
tise by demo projects. The health benefits
will be the same regardless of why a per-
son walks or bikes, but the reduction in
automobile trips will only be accomplished
if these modes substitute automobile driv-
ing.
Poor accident statistics
The area ranked number two, “Precondi-
tions for and safety implications of large
increases in walking and cycling”, deals
with what the preconditions should be for
a massive increase in the number of peo-
ple choosing to walk or ride bikes. The
purpose could be to provide a supporting
tool for the selection and implementation
of measures aiming to promote safe walk-
ing and cycling.
The area “Quantifying death, injury and
other harm arising from walking and cy-
Promoting safe walking and cycling
Example of winter maintenance procedures favouring automobile traffic.
PHOTO: LARS LEDEN
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 1 3
TECHNICAL RESEARCH CENTRE OF FINLAND (VTT), COMMUNITIES AND INFRASTRUCTURE
cling without the involvement of a motor
vehicle or in unreported collisions with
motor vehicles, and categorising the ways
and circumstances in which they arise”,
was ranked number three. It is well known
that police-reported statistics on pedestrian
and cyclist accidents are incomplete and
biased and therefore often not a very ap-
propriate basis for work aiming at promot-
ing safe walking and cycling. Hospital-
based statistics should be used to a greater
extent.
Helmet use
“To monitor traffic behaviour for differ-
ent age and road user groups and their use
of devices such as helmets, reflectors etc”
was ranked number four. It is suggested
that a new comprehensive technique is
used. A base for this is presented by
Johansson et al (1999). There obviously
would be huge advantages if a uniform
technique were used not only in Finland
but eventually all over Europe.
Australian research has shown that re-
quiring helmet use in the short run can re-
Project name Priority Experts EmailHow walking and cycling can form an integraland attractive part of daily travel bya. improved maintenance procedures 7 Kimmo Rönkä, LT-Konsultit Oy [email protected]
Anna Bergström, VTI/KTH [email protected]. improved intermodality 7 Maija Vähä-Rahka, Traffic League, [email protected]
Finland
c. other means (infrastructure see below) 14 Pekka Oja, UKK-instituutti [email protected] Nilsson, LTH, Sweden [email protected]
Preconditions for and safety implications of l 2 Lars Ekman, LTH, Sweden [email protected] increases in walking and cycling George Kanellaidis, NTUA, Greece [email protected] makes a route attractive or unattractive 9 Mikko Räsänen, Likenneturva, Finland [email protected] pedestrians and cyclists including subjective Christer Ljungberg, Trivector, Sweden [email protected] objective riskImplications for pedestrians and cyclists of 11 Risto Kulmala, VTT, Finland [email protected] of the intelligent transport Andras Varhelyi, LTH, Sweden [email protected] effects and risks of walking and cycling 12 Liisa Hakamies_Blomqvist, VTI, Sweden [email protected] the elderly Agneta Ståhl, LTH, Sweden [email protected]
Kimmo Rönkä, LT konsultit, Finland [email protected] mechanism whereby walking and cycling 5 Lars Ekman, LTH, Sweden [email protected] safer where there are more pedestrians andcyclists aboutThe incidence of injury as road users to people 19 Jörgen Lundälv, Norrlands universitets- [email protected] reduced mobility sjukhus, Sweden
duce ridership (Finch et al, 1993). On the
other hand, the long-term effect on
ridership may be positive since higher
safety should lead to higher participation.
Another concern is that there is a possibil-
ity that risks will not be decreased as much
as anticipated because of risk-compensa-
tion behaviour (risk homeostasis). In recent
years, helmets meeting the needs of cy-
clists have been developed and helmets
may be a natural part of the cyclists’ equip-
ment. This already seems to be the case in
many cities in Finland and Sweden. In
1997 the use of helmets was almost 40%
in the Helsinki Metropolitan area and in the
Stockholm area. However, for the rest of
Finland the figure was “only” 14%, which
is still better than the 7.9% for the rest of
Sweden (Nolén, 1998 and Parkkari, 2000).
Information about safety and promotion
activities at schools and work have been
important instruments in supporting peo-
ple who want to use a helmet.
Greater flow, less risks
The area “The mechanism whereby walk-
ing and cycling are safer where there are
more pedestrians and cyclists about” was
ranked number five. Rare events are often
dangerous. Risk decreases with increasing
pedestrian and cycle flows, as discussed
for example by Ekman (1996). However,
the mechanism behind this is not well un-
derstood. More knowledge could be an
important step toward improved road
safety.
“To improve cycle helmets to protect
the face, to fit better, and to be more attrac-
tive to users” was ranked number six.
Improved maintenance
Exploring “How walking and cycling can
form an integral and attractive part of daily
travel by improved maintenance proce-
dures” was ranked number seven. The best
practice in Finland is found in Oulu, where
good infrastructure and maintenance pro-
cedures (including winter maintenance)
have given a high annual modal share for
biking. Of all trips in Oulu 25% are cycle
Table 1. Deeper understanding of the necessary change
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20001 4
Example of design promoting safe cycling.
Project name Priority Experts EmailHow walking and cycling can form an 1 Eero Pasanen, City of Helsinki, Finland [email protected] and attractive part of daily Lars Leden, VTT, Finland [email protected] by demo projectsComparing the risks of travel on foot orby cycle with those of realistic travelalternatives in a range of specific situations 10 Hans Thulin, VTI, Sweden [email protected] death, injury and other harm 3 Ulf Björnstig, Norrlands universitetssjukhus, [email protected] from walking and cycling without Swedenthe involvement of a motor vehicle or in Per-Olof Kroon, Borås hospital, Sweden [email protected] collisions with motor vehicles, Birte Landorph, Odense Universitetshospital, [email protected] categorizing the ways and circum- Ulykkesanalysegruppen, Denmarkstances in which they ariseMonitoring the amounts of walking and 13 Matti Pursula, HUT, Finland [email protected] locally in urban areasAssessing patterns of potential movement 16 Matti Keränen, Viatek, Finland [email protected] foot or bicycle in each part of anurban areaMonitoring the traffic behaviour for different 4 Kalle Parkari, Liikenneturva, Finland [email protected] and road user groups and use of Lars Leden, VTT, Finland [email protected] such as helmets, reflectors etcMonitoring the effectiveness of education, 15 Roelof Wittink, I-ce, the Netherlands [email protected], publicity, road user training and Pirkko Rämä, VTT, Finland [email protected] of professionals relevant to the safety Matti Järvinen, Liikenneturva, Finland [email protected] walking and cycling
trips, compared with the average annual
share for Finland of 12% and 9% for Hel-
sinki (Schollaert and Coppieters, 1997). In
Helsinki, cycling mainly takes place in
May-September, even though Helsinki has
850 km of cycle tracks. One important rea-
son is that winter maintenance procedures
favour automobile traffic (Figure 1).
“How walking and cycling can form an
integral and attractive part of daily travel
by improved intermodality” also ranked
seventh. Safe routes to and from public
transportation and secure bicycle parking
facilities are obvious necessities if one
desires to see more people ride bicycles to
and from bus and train terminals. Even
more important may be ensuring that fu-
ture planning keeps densities high and dis-
tances short so that these systems can be
supported.
TECHNICAL RESEARCH CENTRE OF FINLAND (VTT), COMMUNITIES AND INFRASTRUCTURE
Table 2. Fuller quantification of the problem and of progress made
PHOTO: EDINBURG COUNCIL
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 1 5
Article specially written for NR&TR by Per
Gårder (Orono, Maine, USA) and Lars
Leden (VTT, Finland).
Acknowledgement: We would like to
thank all the experts who answered our
questionnaires, Harri Peltola (co-
ordinator of the overall research program,)
for his fruitful co-operation, and the com-
mittee members of the European Transport
Safety Council for their excellent work.
Literature:
Ekman, L., 1996. On the Treatment of
Flow in Traffic Safety Analysis a non-
parametric approach applied on vulner-
able road users. University of Lund
Lund Institute of Technology. Depart-
ment of Traffic Planning and Engineer-
ing. Bulletin 136.
Finch, C.F., Heiman, L. & Neiger, D.,
1993. Bicycle use and helmet wearing
rates in Melbourne 1987 - 1992: The in-
fluence of the helmet wearing law.
Monash university. Report 1993/02.
Referenced by Martinsson, T., 1996.
Trafiksäkerhetsreform Användning av
cykelhjälm. Borlänge, Vägverket.
Arbetspapper 1996-02-20.
Günther, R., Ekman, L., Janssen, E.,
Palmer, D., Lemonde De Macedo, A.,
Allsop, R., Herrstedt, L., Michalik, C. &
Fleury, D., Safety of Pedestrians and cy-
clists in urban areas. Brussels. Euro-
pean Transport Safety Council.
Gårder, P. & Leden, L., 2000. Strategic
Project name Priority Experts EmailDevelopment of European standards 17 Christian Wetterberg, Svensk [email protected] safe cycles maskinprovning, SwedenDevelopment of cycle lamps that are 20 Peter Winterman, Shimano Europe, [email protected], reliable and convenient to use The NetherlandSin real cycling conditionsDevelopment of a parents’ cycle for 21 Claes Alstermark, Cycleerope, Sweden [email protected] of young children and Kjell Sture, A. Samuelsson & Co, Sweden [email protected] passengersImprovement of cycle helmets to protect 6 Phil Graitcer, WHO:s Helmet Initiative [email protected] face, to fit better, and to be more Diane C Thompson, Harborview [email protected] to users medical center, US
Brian Chinn, TRL, Great Britain [email protected] possibility of child seats for inter- 22 Claes Tingvall, Swedish National [email protected] use between cars and cycles Road Administration, Sweden
Magnus Petrius, Rex industri AB, Sweden [email protected] Turbell, VTI, Sweden [email protected]
Reduction of head injuries to pedestrians 18 Per Lövsund, Chalmers, Sweden [email protected] cyclists from striking the windscreens Graham Lawrence, TRL, Great Britain [email protected] A-pillars of cars
Research fund prioritisations
Finally, it is obvious that research alloca-
tion should not be based solely on the opin-
ion of a relatively small number of experts.
However, it is our opinion that these re-
sults should be an important part of re-
search fund prioritisation in Finland and
Europe in coming years. Furthermore, re-
search already underway should be con-
tinued if there are promising results in
those areas. Participation in international
programs may also be important–even if
those areas have low rank—so that national
interests are safe-guarded.
R & D Program for Safe Mobility. Pro-
moting safe walking and cycling. Report
no 14 from the SRS project. VTT Com-
munities and Infrastructure. Research
Report 568/2000.
Johansson, C. Leden, L., Nilsson, K.,
Wilhelmsson, O. & Gårder, G., 2000.
Towards a safe traffic environment for
children - a starting point, Lund,
ICTCT, Kaiserslautern, 1999.
Nolén, S., 1998. Tio års
cykelhjälmsanvändning i Sverige.
Resultat från observationsstudier 1988-
1997 med tonvikt på 1997 års
mätresultat. VTI meddelande 844, 1998.
Parkkari, Kalle, 2000. E mail 10 April
2000.
Schollaert, U. & Coppieters, M.-C.,
1997. Transport Demand od Modes not
covered in International Transport Sta-
tistics. Cycling. European Cyclists’ Fed-
eration (ECF). European Union (con-
tract n° E1-B96-B2 7040-SIN 6051-
ETU)
TECHNICAL RESEARCH CENTRE OF FINLAND (VTT), COMMUNITIES AND INFRASTRUCTURE
Table 3. Safer cycles and further crash protection
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20001 6
NORWEGIAN PUBLIC ROADS ADMINISTRATION (NPRA)
The strengthening of concrete
structures with fibre reinforced
composites is a new field in rapid
development. A number of new
projects have been started in order
to improve understanding and
develop design standards. The
results so far have been positive,
and strengthening with carbon
fibres will in many cases be a simple
and effective solution.
There is an increasing need for a way to
strengthen concrete structures, either as a
result of damage or due to a need for in-
creased loading because of rebuilding or
change of use.
Road authorities in many European coun-
tries are reporting an ever increasing de-
gree of damage to bridges caused by dete-
rioration and increasing traffic loads.
Subsequently there has emerged a need to
strengthen bridges such that an acceptable
safety margin is upheld. At the same time
there is a requirement that the repair and
strengthening work is required to be car-
ried out:
• in the most economic way
• without reduction in traffic flow
• in a way that preserves the aesthetic
properties of the structure.
Strengthening by the use of Fibre Rein-
forced Polymers (FRP) is an interesting
possibility. Fibre reinforced polymers con-
sist of high strength fibres, typically car-
bon, aramid and glass, contained within
an epoxy matrix.
Stimulus for the constructionindustry
FRP-composites are traditionally associ-
ated with the aircraft and automobile in-
dustries as well as extreme activities in the
marine environment such as sailing. De-
spite more than 25 years research into com-
posite materials experience with their use
in the construction industry is still limited.
This is about to change. Lower material
costs have now made it possible to take
advantage of composite materials for
strengthening and upgrading of concrete
structures.
The use of FRP-composites has a great
potential because fibre reinforcement has
low weight, high strength, is thin and can
be installed quickly by gluing. It is claimed
that FRP-composites will provide a stimuli
for the construction industry analogous to
the introduction of reinforced concrete at
the beginning of the last century. This,
however, remains to be seen.
The method of construction is either the
“wrap” method where a woven fabric mat
about 0.15 mm thick is impregnated with
epoxy and glued to the structure. Alterna-
tively a carbon fibre reinforced plate 1-2
mm thick can be glued to the structure.
Experimental program
To be able to evaluate whether strength-
ening with fibre reinforced plates or wo-
ven fibre mats is an acceptable mainte-
nance method, practical testing is being
carried out in a collaboration between
structure owners, suppliers, contractors
and research institutions:
1) Strengthening of bridge beams with
carbon fibres reinforced composites.
2) Strengthening / sealing of bridge col-
umns by wrapping in impregnated woven
carbon fibre mats.
The tests are being carried out as part of
the research project “Concrete Structures
Strengthening with carbon fibres
Figure 1. From the demolition of Isakveien bridge - The work was carried out at night to avoid
disruption to railway traffic.
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 1 7
NORWEGIAN PUBLIC ROADS ADMINISTRATION (NPRA)
Life Cycle Project”. The following is a
brief description of the activities. Further
details are given in two rapport’s [1] and
[2] which will be published later in the
autumn.
Strengthening
During the controlled demolition of
Isakveien bridge in Lillestrøm (see figure
1), Akershus County Road Authority re-
moved two 11.2 m long Double T (DT)
beams from the 35 year old bridge and
transported these to the Department of
Structural Engineering, at the Norwegian
Technical University (NTNU) in
Trondheim. Each of the DT beams, which
had a 100 mm structural overlay (cast
insitu bridge deck), was divided lengthwise
to produce in all 4 T beams with structural
overlay.
Before and during the demolition work
a condition survey was performed. Table 1
gives a summary of the findings, as to du-
rability parametres. The conditions were
generally better in spans than at the beam
supports. This is most likely due to intrusion
of water and inadequate bond between the
overlay and the DT-beams near the col-
umns. The bond strengths between overlay
and DT-beams were tested at different lo-
cations. As shown in figure 2, the failure
also occured outside the interface area.
Failure values
The beam cross sections are shown in fig-
ure 3. The design strength of the concrete
used in the pre-cast beams was C55 (old
Norwegian grade B600) and C25 (B300)
for the structural overlay. The beam was
pre-stressed with 40 no. Ø4 mm St 1600/
1800 strands in the web and 14 no. Ø4 mm
strands in the flange. Shear reinforcement
consisted of Ø8 mm stirrups at 300 mm
centres.
Beam no.’s 1 and 2, without FRP-
strengthening, were tested to failure for
moment and shear respectively. The fol-
lowing failure values were recorded:
Beam no. 1:
Recorded moment at failure:Mfail
= 600 kNm
Beam no. 2:
Recorded shear at failure:Vfail
= 324 kN.
The achieved moment capacity was 23 %
higher than the sectional capacity, includ-
ing the overlay, calculated according to the
Norwegian Standard NS 3473 when the
material coefficients are set to 1.0. Like-
wise the recorded shear capacity was 104
% higher than the value calculated accord-
ing to NS 3473.
There was full composite action be-
tween the pre-cast beam and the overlay
during the entire duration of the test. The
calculated capacities for the section with
and without the overlay shows that the
addition of the overlay in this case leads to
an increase in section capacity of about
30%.
Strengthend beams
The remaining two beams were strength-
ened with longitudinal carbon fibre com-
posite plates of type SIKA CarboDur S
2850/3050 which have an average meas-
ured failure tensile strength of 3050 N/
mm2 and a Young’s modulus of 165 GPa.
The carbon fibre plates had a cross sec-
tional area of 108 and 216 mm2 for beams
3 and 4 respectively. Beam no. 3 was tested
to failure in bending, while beam no. 4,
which was to be tested in shear, had a com-
bined moment / shear failure.
Figure 2. Testing of
adhesion between the
pre-cast beam and
structural overlay by
the pull-off test. As
can be seen, failure
did not always occur
between the beam and
overlay, indicating
good bond between
the two.
Figure 3. Cross section of the test beams. The original Double T elements were cut in
two lengthwise.
Beam no. 3
p, maks
t t, mean
p
po,
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20001 8
NORWEGIAN PUBLIC ROADS ADMINISTRATION (NPRA)
Element / Cd Cover Potential Rust grade Commentslocation [mm] [mm] field value
Edge beam / 0 38 -280 B – C Chiselling. Potential fieldA2 value -250 – -410 for edge beam,
6 m length around A2
Parapet / 2 – 3 10 – 20 -160 – -355 B – C Stirrups (cover 10 mm), meshA2 north (cover 20 mm), determined by chiselling
Parapet / 0 – 5 11 – 22 -175 – -305 B – C Stirrups (cover 11 mm), meshA2 south (cover 22 mm), determined by chiselling
DT element > 30 5 / 30 -185 – -405 C At the end of the DT element (end of stirrups/ (end of element) the carbonation depth was > 30 (in toelement) cable cables). The potential field value became rap
idly more positive towards the middle of thebeam before sinking again towardsthe other end.
The adhesion between the pre-cast beam and structural overlay (tensile strength ) varied from 1.2 to 1.8 MPa (average 1.5 MPa)with the rupture occurring both in the pre-cast unit and in the interface between the beam and overlay.
Cd: Carbonation depthPotential field value: mV against Cu/CuSO4Rust grade (as defined in Norwegian Public Roads Authority Hand book 136 – Bridge inspection guide):
A = no rust,B = small amounts of surface rust,C = Evenly distributed surface rust,D = scaling rust with a clear reduction in cross sectionE = pitting corrosion.
Recorded failure values were:Beam no. 3:
Additional reinforcement AFRP
= 108 mm2
Recorded moment at failure Mfail
= 751 kNm.
Beam no. 4:
Additional reinforcement AFRP
= 216 mm2
Recorded moment at failure Mfail
= 800 kNm
Recorded shear at failure Vfail
= 214 kN.
Beam no. 4 cannot be directly compared
with the control value for shear, beam
no. 2, because of a difference in the load
arrangement.
The comparison between the strength-
ened and unstrengthened beams shows
that strengthening with the FRP plates
gave an increase in moment capacity of 25
and 33 % for beams no.’s 3 and 4 respec-
tively. This increase is in good agreement
with the additional area of reinforcement
that the FRP plates represent.
The failure mechanism for the strength-
ened beams, however, was more brittle.
This can be explained in part by the in-
crease in the area of reinforcement and
partly because in the final stages of failure
a lamination crack developed in the web
just above the prestressing strands.
An additional advantage was that FRP
strengthening lead to an increased stiffness
for the loading levels that are representa-
tive for the serviceability limit state.
Strengthening and sealing
As part of the development of simple meth-
ods for the repair of bridge columns which
have been damaged either as a result of
insufficient durability or increased load-
ing, test loading of columns strengthened
with woven carbon fibre fabric sheets was
carried out at SINTEF Civil and Environ-
mental Engineering in Trondheim. The ap-
proach is relevant to bridge columns with
considerable cracking for example as a re-
sult of Alkali Aggregate Reaction (AAR)
damage where there is a danger of corro-
sion of the reinforcement.
The aim of the activity is to test the
strengthening effects of wrapping columns
in woven carbon fibre fabric sheets, as well
as investigating the secondary effect of
sealing the concrete surface.
An experimental laboratory program
has been carried out where 4 columns have
been tested to failure under a centrally ap-
plied load. The columns were 2.8 m long
and had a diameter of 330 mm. The verti-
cal reinforcement in the middle portion of
the column has been lapped with a lap
length of 300 mm, which is about 1/4 of that
required by NS 3473.
Column S1, the reference column, was
a concrete column where the vertical rein-
forcement was without stirrups in the mid-
dle 1 m section. Column S2 was the same
as S1 but with the addition of 5 no. Ø8 mm
stirrups placed at 130 mm centres in the
middle 620 mm section. Columns S3 and
S4 were of the same construction as S1 but
with strengthening in the form of one and
two layers respectively of woven carbon
Table 1: Extract of condition data from Isakveien bridge prior to demolition.
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 1 9
NORWEGIAN PUBLIC ROADS ADMINISTRATION (NPRA)
References
[1] Takacs, Peter F. & Kanstad, Terje:
Strengthening Prestressed Con-
crete Beams with Carbon Fibre
Reinforced Polymer Plates. NTNU-
rapport, 2000-08-16 (Provisional):
Client: Norwegian Public Roads
Administration & SIKA Norway
AS. Trondheim, NTNU 2000.
[2] Thorenfeldt, Erik & Øverli, Jan
Arve: Forsterkning av betongs-
øyler med karbonfibervev.
(Strengthening of bridge columns
with woven carbon fibre materials)
SINTEF-rapport, 2000-07-14
(Provisional): Client: Norwegian
Public Roads Administration,
Trondheim, SINTEF 2000.
[3] SIKA Norway AS.
Dimensjoneringsveiledning for
Sika CarboDur - laminater
(CarboDur laminates Design
procedure - adapted to Norwegian
conditions). Hagan 1999.
The article is written by Finn Fluge & Ian
Markey.
Norwegian Public Roads Administration,
Road Technology Department (NRRL).
fibre fabric sheet of type SIKA Wrap with
a thickness of 0.13 mm.
The following axial loads were recorded
at failure:
• Column S1 F = 2177 kN
• Column S2 F = 2195 kN
• Column S3 F = 2633 kN
• Column S4 F = 3281 kN.
Wrapping with one layer of woven carbon
fibre fabric increased the failure load by
21 %, while two layers gave an increase
of 51 %.
The fibre reinforced columns were
much more ductile than the reference col-
umn. Concrete strain at failure was 1.5 ‰
for column S1 and 5 ‰ for column S4.
The effect of external fibre reinforce-
ment is considerable, but cannot be taken
full advantage of when repairing columns
which are already under load.
The application of carbon fibre woven
sheets proved to be a relatively simple op-
eration.
Construction directives
In addition to the aforementioned test-
ing, the Norwegian Armed Forces Build-
ing Service (FBT) have begun a testing
program at SINTEF Civil and Environ-
mental Engineering where the aim is to
document the bonding properties be-
tween the glued carbon fibre composites
and the concrete surface.
This is naturally encompassed by the
work to establish the foundation needed
when drawing up new standards. The
most important problems which have to
be addressed are:
• Choice of material, design and
method of construction for varying
uses
• Interaction between the glued fibre
plate and the concrete structure
• The connection between cracking in
the concrete and stresses in the fibre
composite
• Bond and anchorage lengths
• Failure mechanisms
• Ductility and the possibility of brit-
tle failure
• Durability.
A design guide has been published in
Sweden covering the strengthening of
concrete structures with carbon fibre
composites, as part of
the Swedish bridge
design standards.
Norwegian guide-lines
At present there are no
such guidelines pub-
lished in Norway.
There does, however,
exist different design
guides, for example
[3], published by
manufacturers of fibre
composites, but these
guides are not stand-
ardised (specific to
manufacturers prod-
ucts) and do not take into account the
choice of different fibre materials, glue
and methods of construction.
In order to remedy this situation, a
joint project has been started, led by
Norconsult, where the aim is to draw up
a Norwegian Concrete Association pub-
lication on guidelines for strengthening
of concrete structures. The results from
the Concrete Structures Life Cycle
Project study will be made available for
this work.
Figure 4: Testing of carbon fibre reinforced beam.
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20002 0
The standards of Russian road
design and Russian road construc-
tion materials must be harmonised
with the standards that apply, or are
being drawn up, in Europe. The
harmonisation project is led by a
Swedish consortium comprising
Sweco International, SweRoad and
VTI.
Large sections of the Russian infrastruc-
ture are substandard. Roads are breaking
up; one of the reasons is that bitumen and
the road pavement are of low quality.
Traffic, and the number of traffic acci-
dents, are increasing.
Commerce also suffers.
A catch-22 situation
What we are facing is a catch-22 situation:
The crisis in the Russian economy results
in the deterioration of the infrastructure,
which, in turn, causes the economic prob-
lems that result in lack of money to im-
prove the infrastructure...
Russia is a great potential market for
enterprises in the European Union coun-
tries. It has therefore been decided to fi-
nance a project which is a first stage in im-
proving the road network in that huge
country in the east.
Several countries in Europe competed
for this project. It was the Swedish consor-
tium, with Sweco as the leading partner,
that succeeded.
Tacis – an EU programme
The consortium comprises Sweco Interna-
tional, SweRoad (i.e. the Swedish Road
Administration) and VTI. Technische
Prüfanstalt of Vienna, Austria, is also a
part, although a minor one, of this other-
wise wholly Swedish consortium.
– It was in really hard competition with
several other consortia that we got this
project, says Kent Gustafson at VTI.
– For example, we have “beaten” Fin-
land, in spite of the great advantage the
Finns had owing to their former coopera-
tion with the Russians.
Kent Gustafson, together with Safwat
Said, is the representative of VTI in the
harmonisation project. Safwat Said was in
Moscow in September to meet representa-
tives of the Russian Road Administration
and the Ministry of Communications.
– In formal terms, this project comes
under an EU programme called TACIS,
points out Safwat Said.
Cooperation with CEN
The objective, to start with, is to review
Russian standards. These will then be com-
pared and harmonised with the standards
that apply in Europe. It is desirable that all
should have the same units of measure-
ment and dimensions as far as this is fea-
sible, but if this cannot be done the units
must at least be comparable.
This is not quite so simple, since stand-
ards are not yet the same in the whole Eu-
ropean Union, but the European Commit-
tee for Standardisation (CEN) is coordinat-
ing a harmonisation process.
– The Russian project will therefore be
conducted in close cooperation with CEN,
says Kent Gustafson.
Purchase of instruments
The principal contribution of VTI will be
to make comparative studies regarding
laboratory and field methods. This work
will be done both in Moscow (at the Road,
Vehicle and Transport Research Institute,
VTI supports better roads in RussiaSWEDISH NATIONAL ROAD AND TRANSPORT RESEARCH INSTITUTE (VTI)
Kent Gustafson, Professor
Nikolay V. Bistrov (Laboratory
Director at MADI) and Leif Viman
(VTI) during a visit to Russia.
– A relatively large proportion of
the work will be done in Moscow,
but Russian laboratory staff will
also come here to Linköping, says
Kent Gustafson.
PHOTO: VTI
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 2 1
SWEDISH NATIONAL ROAD AND TRANSPORT RESEARCH INSTITUTE (VTI)
MADI), and in Linköping.
– Our impression is that the theoretical
expertise of the Russians is very high, but
that they do not have the optimum facili-
ties to put their knowledge to practical use,
says Kent Gustafson.
– They have primitive laboratories and
little scope.
The intention is that at the end of the
project the staff of Russian laboratories
will be trained in European methods of
analysis. In this also VTI will play a ma-
jor part.
– We will work as consultants in Rus-
sia, says Kent Gustafson. The Russian staff
will also have access to instruments of
CEN standard. In the budget, funds have
been allocated for the purchase of such
instruments.
The project is intended to extend over
two years. It must therefore be finished in
the summer of 2002.
– I do not think that we will solve all the
problems in these two years, but it is at
least the first step on the way, says Kent
Gustafson.
Both he and Safwat Said are looking
forward to working with the Russians.
– Sweco has a representative in Russia
who is familiar with Russian conditions.
Many other necessary contacts have also
been established. I believe this means that
we will not be obstructed, says Kent
Gustafson.
– Yes, we have the gateways we need.
We have no feelings of insecurity at all,
adds Safwat Said.
The beginning of something new
When VTI agreed to being part of the
Sweco consortium, this meant entering a
completely new area. VTI has not previ-
ously been involved in any projects of this
kind. On some occasions, however, VTI
has seconded staff to e.g. Costa Rica, Es-
tonia and Indonesia.
Does this mean that VTI is extending its
activities?
– Yes, we could perhaps say that, smiles
Kent Gustafson. And this may be only a
beginning. We have already been asked
whether we would participate in further
projects within the framework of the same
EU programme.
Catarina Gisby/Redakta
One example of the differences between
equipment in Russia and the rest of Europe.
In Russia the screen apertures are round,
while in Europe they are square.
In Moscow the roads are perhaps not so bad, but one does not have to travel far outside the metropolis to note the very poor state of the
Russian road network.
PHOTO: VTI
PHOTO: VTI, KENT GUSTAFSON
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20002 2
SWEDISH NATIONAL ROAD AND TRANSPORT RESEARCH INSTITUTE (VTI)
It is almost 70 times more danger-
ous in Ghana than in Sweden to be
in traffic. In order to reduce the
large number of traffic fatalities
and injuries, Ghana has turned to
Sweden and VTI for help.
– The requirements for getting a driving
licence must be increased to improve traf-
fic safety, says Birger Nygaard, researcher
at VTI.
The standard of Ghanaian drivers has
for many years been considered low, and
this has a strong negative effect on traffic
safety in Ghana. The general level of edu-
cation of the population is low, and almost
one half are illiterate. Every year, a large
number of people are killed in traffic in
Ghana, and even more are seriously in-
jured. This low driving standard has reper-
cussions not only for the individual driv-
ers but also for the whole country. National
economy is badly affected by the high
medical care costs, and this means that
development is retarded since a large pro-
portion of the country’s money is used up
by the high – and apparently unnecessar-
ily high - costs of caring for those injured
and killed in traffic.
High accident risk
There are no exact figures as to how many
are killed and injured in traffic in Ghana,
but the risk of being killed in traffic is about
70 times greater than in Sweden. This is
in spite of the fact that the estimated
number of those with a driving licence is
only between one and one and a half mil-
lion, and there are only about 300 000 ve-
hicles in the country that has a population
nearly twice that of Sweden.
– Quite simply, it is not possible to ob-
tain more exact figures. The vehicle and
driving licence records are kept manually
and consist mostly of piles of paper divided
between the 21 DVLA offices in Ghana,
says Birger Nygaard, project manager for
the traffic safety project in Ghana.
Computerisation of the register is also one
of the main tasks of the traffic safety
project which VTI is running in Ghana.
A driving licence feeds the family
Ghana is a very poor country and only
about one half of the population has a paid
job. This means that the number of those
who can afford lessons in the few driving
schools is very low. To train for a driving
licence at a driving school in Ghana costs
about 350 000 Cedi which corresponds to
about 800 SEK. The average monthly
wage in Ghana is 400–600 SEK.
But a driving licence can in many cases
decide the survival of a whole family, and
many people therefore get a driving licence
without going to a driving school, which
poses a problem for traffic safety.
– In a developing country like Ghana,
all members of a family must help earn
money for the family, says Birger Nygaard.
Striking a balance
For many people, a driving licence repre-
sents entry to the labour market, since be-
ing a driver is one of the most common jobs
in Ghana for somebody who has no school
education. As a driver, one can earn a few
extra Cedi so that all members of the fam-
ily will have enough to eat each day.
Driver training programme in Ghana
PHOTO: VTI
PHOTO: VTI
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 2 3
SWEDISH NATIONAL ROAD AND TRANSPORT RESEARCH INSTITUTE (VTI)
– This is a dilemma for us when it comes
to tightening up the requirements for a
driving licence, emphasises Birger
Nygaard.
– While we want to improve the safety
of traffic users in Ghana as quickly as pos-
sible, we must also bear in mind what con-
sequences this will have for the situation
of individuals.
Oral driving tests
Theoretical and practical driving tests in
Ghana are markedly different from those
in Sweden. Among other things, the theo-
retical test is mostly oral since illiteracy is
very high, about half the population can
neither read nor write. The situation among
younger people seems better, however,
since most go to primary school at least
for a few years.
At present, the theoretical test contains
a few questions about the meaning of traf-
fic signs. If the person manages to answer
most of the ten to twelve questions, he or
she is considered to have passed. The prac-
tical test is similar, people have to drive a
short distance on an ordinary road, and if
they manage this, the test is deemed satis-
factory.
– To create a driver training programme
which can be used by all irrespective of
whether they can read and write is a com-
pletely new experience both for me and for
VTI and Sweden, says Birger Nygaard.
New system in 2001
The new driver training programme which
VTI is helping Ghana develop will place
much greater emphasis on traffic safety
issues than the present system. The require-
ments which people must satisfy to get a
driving licence in Ghana today are not suf-
ficient to prepare drivers for the heavy and
complex traffic they will encounter, mainly
in the large cities. The intention is that the
new driver training system will gradually
come into force from the middle of 2001.
“Old” and “new” driving licences
The development project in Ghana is only
in its introductory phase, it was started
about one year ago on the basis of agree-
ments on the overriding goals and the
means of attaining these.
During the spring and summer of 2000
a large pictorial archive from Ghanaian
traffic environments was built up. These
pictures will be used to illustrate theoreti-
cal tests, text books and TV campaigns. In
the autumn and winter of 2000 courses will
be held for driver examiners and driving
school instructors. New teaching material
will also be produced that places greater
emphasis on traffic safety issues than was
the case when people learned the meaning
of traffic signs by heart. This will be fol-
lowed by information campaigns on TV
and radio, and it is expected that in one
year, in the middle of 2001, a start can be
made on introducing the new regulations
and requirements, and also a completely
new driving licence system. In order to
come to grips with the increasing problem
of illicit driving licences, Ghana has al-
ready this year introduced a new type of
plastic driving licence, similar to the Swed-
ish licence, that cannot be forged.
– One problem that we are still trying
to solve is what to do with those who al-
ready have a driving licence, says Birger
Nygaard.
Since there is no functioning register of
people who have a driving licence, it is not
possible, or indeed desirable, to replace ex-
isting licences by new ones. Nor is it pos-
sible to require all the “old” driving licence
holders to take a new test, since it is not
known who has a driving licence.
– We are hoping for support from the
large companies in Ghana which need to
employ drivers. If we could persuade them
to pay for driver training for their employ-
ees, this would be a great step forward. And
it appears that companies in Ghana are
very interested in spending money on train-
ing, says Birger Nygaard.
Aid from SIDA and the World Bank
When the Ghanaian authorities decided to
ask for assistance in developing their driver
training system and the requirements for
getting a driving licence, they wanted to
try something new instead of turning to
their former colonial power, Great Britain.
Ghana applied to the World Bank for
money to modernise and develop the pub-
lic sector and the DVLA offices, and to
the Swedish International Development
Authority SIDA for help in appointing VTI
as expert consultant. Representatives of the
Ghanaian traffic authorities have on sev-
eral occasions visited VTI in different
matters, for instance for traffic safety
courses, and as a result the Ghanaian gov-
ernment decided to approach VTI for ex-
pert assistance.
– It is very unusual for VTI to be asked
to manage such a large project, says Birger
Nygaard, since VTI has not the broad ex-
pertise that is needed in this case. We there-
fore collaborate with external experts, such
as SweRoad and Lernia, which supply the
expertise that VTI lacks.
PHOTO: VTI
The driving license records are kept manually and consist mostly of piles of paper.
PHOTO: VTI
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20002 4
Annotated reports from the Danish Road Directorate (DRD)
The Road Directorate has published a new
report in Danish describing the condition
and development of the National High-
ways in Denmark for the year 1999. The
report deals with themes regarding traffic
volumes, transport quality, road and bridge
maintenance conditions, service facilities,
road safety, environmental conditions and
road accounts.
Like its predecessor ”National roads
1998” the new report consists of maps,
graphs, tables and text, which aim to give
the reader a general overview of the present
Author: Søren BrønchenburgSeries: Report No. 201Language: Danish
condition and development of the national
highway network. The report is also avail-
able in electronic form (HTML and PDF)
from the Danish Road Directorate´s web
site www.vd.dk under Publications. Title:
“Statsvejnettet 1999: Nøgleinformationer
om statsvejnettets tilstand og udvikling”.
Published in Denmark, August 2000.
Key information on the condition and development of thenational highway network in Denmark
The coastal bridge projectMarine structures involve substantial in-
vestments for construction as well as re-
pairs during their service life. Danish ma-
rine bridge structures were built in the
period 1936-1985. Danish bridge piers in
seawater are subject to a high risk of cor-
rosion damage due to the high chloride
content in the Danish seawater.
The Danish Road Directorate has from
1995-1999 investigated their bridge struc-
tures in order to evaluate the probability of
corrosion damage at the time of investiga-
tion and in future. This report includes a
presentation of the investigation method-
ology and the results of the investigations.
Furthermore the bridges are given a prior-
ity depending on their present condition
and thus whether a special investigation or
merely a basic investigation program
would apply in future.
Subsequently an overall basic investi-
gation programme has been suggested for
future use, where details on number and
Authors: Erik Stolzner, Birgit Buhr,Finn Jensen, AsgerKnudsen, Ruth Sørensen,Danish Road Directorate,Bridge Department
Series: Rapport nr. 198, 2000Language: Danish
location of tests are given together with
specifications on test methods to be used.
The project’s aim is to monitor the devel-
opment in urban air quality in Denmark.
The survey involves 28 roads. The air qual-
ity is calculated using a Nordic perdiction
model called BLB (Beregningsmodel af
Luftkvalitet i Bygader). BLB calculates
levels of CO and NO2. A comparison on
three roads with permanent stations for
monitoring air quality shows that calcu-
lated values of both CO and NO2 are quite
consistent with the measured values.
The 28 roads together carry the same
amount of traffic from 1985 to 1998. On
access and cross-town roads there has been
a 14 percent increase. There has been a 21
percent decrease in traffic volumes on
main streets in central areas. On main
streets in urban areas the traffic levels have
fluctuated through the period of the survey.
The trend in pollution levels clearly shows
the effect of catalytic converters on passen-
ger cars. The levels of CO have decreased
by altogether 57 percent from 1985 to
1998, and it is unlikely that there are prob-
Traffic and urban air quality - Monitoring and modellingfrom 1985-1998
Authors: Lars Ellebjerg Larsen andLone Reiff, Road Directorate
Series: Rapport 199, 2000Language: Danish
lems in keeping below the WHO’s guide-
line values. The levels of NO2
have de-
creased by 27 percent since 1985, but there
are still fairly high levels on several roads.
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 2 5
Annotated reports from VTT, Communities and Infrastructure, Finland
Author: Kyösti LaukkanenSeries: VTT Communities and Infra-
structure, Contractor Report548/2000
Language: Finnish with English ab-stract
The aim of the study was to find out new
easy-to-use concrete moisture measuring
devices for bridge deck waterproofing
sites. The present methods in use are dry-
ing concrete samples in oven or measur-
ing the relative humidity in holes drilled
into the bridge deck. The research method
was to measure moisture with 13 different
devices in the same concrete samples
stored at laboratory in different humidity
conditions.
The study was carried out by VTT Com-
munities and Infrastructure and VTT
Building Technology and it was ordered by
the Finnish National Road Administration.
Based on the study it was possible to
rank the devices which worked best at
laboratory. Several devices which were
tested were not applicable for measuring
high moisture contents with an adequate
accuracy.
For measuring the moisture content of
concrete the Tramex Concrete Moisture
Encounter gave results that were best com-
parable with the results of the oven drying
method.
Among the test methods based on rela-
tive humidity, a Rotronic AWVC-device
and a test tube method (using a Vaisala
sensor) gave results that were relatively
near to the values measured in holes drilled
in concrete.
These test results are valid only in the
constant laboratory climate conditions
used in the study. On a bridge site also
many variables (e.g. temperature changes,
rain, wind and in old bridges chlorides)
affect the results. That is why the study
should be continued using the three meth-
ods with best laboratory results in real
bridge site climate conditions.
An easy to use device for measur-
ing moisture in concrete.
Finnish Rail Administration (RHK) has
started to monitor all railway level cross-
ings on their rails. The monitoring has al-
ready been made on five rail sections
(about 450 km and 325 railway level
crossings) and will continue for some
years.
After the field studies the recommen-
dations for countermeasures to improve
traffic safety at monitored railway level
crossings were made. The countermeas-
ures were classified to be carried out im-
mediately, soon or later. The countermeas-
ures to be carried out immediately make a
railway level crossing safe to enter. Exam-
ples of these countermeasures were e.g.
restrictions for articulated vehicles, speed
limits for trains or clearing the vegetation
to improve sight distances. A countermeas-
ure to be carried out soon (within a year)
could be equipping the level crossing with
half-barriers and later building of grade
Concrete moisture measuring methods for bridge construction site
Traffic safety at railway level crossings
Author: Kirsi Pajunen, Matti AnilaSeries: VTT Communities and Infra-
structure, Contractor Re-ports 539 and 543 / 2000
Language: Finnish with English Ab-stract
separated crossing or a new road connec-
tion. A computer program called ARC
(Audit of Railway level Crossings) was
developed to view all monitored railway
level crossings.
We have also described the problem of
traffic safety at railroad level crossings.
Almost one hundred different counter-
measures to improve traffic safety at rail-
road level crossings were collected from
literature and interviews of experts as a
toolbox for RHK. The pros and cons of the
countermeasures and their applicability to
the conditions in Finland were assessed.
PHOTO: KYÖSTI LAUKKANEN
PHOTO: MATTI ANILA
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20002 6
A package of co-ordinated measures in
order to develop public transport has been
carried out in Kongsvinger, a small town
in the eastern part of Norway.
This report summarises the short-term
effects of the measures as they appear in
surveys of train and bus passengers, and
among the elderly, which is a target group
for this project.
The main conclusions are:
Package of measures ”Transport for all in Kongsvinger”– New passengers were captured, and
existing passengers travelled more.
– Among train users the express bus,
rather than the car, had to a large extent
become the alternative mode.
– Parts of the long distance travellers
who had a car available chose public trans-
port because it was more comfortable.
– Passengers felt to a great extent that
the measures represented a positive devel-
opment of the relevant quality factors.
–The infrastructure measures made con-
siderable improvements for the public
transport operations and enabled the deliv-
ery of improved services.
Authors: Kjartan SælensmindeSeries: TØI report 491/2000Language: English
Annotated reports from the Institute of Transport Economics (TØI), Norway
The subject of this thesis is how to value
nonmarket goods when the valuations are
to be used in cost-benefit analysis. Two
different Stated Preference valuation meth-
ods are used in the five papers that consti-
tute the thesis, Stated Choice and Contin-
gent Valuation. A main result in the thesis
is that Stated Choice is a valuation method
that may collect so much data noise that
the valuation results are affected. There-
Valuation of nonmarket goods for use in cost-benefit analyses.fore, the elicitation methods should be
made sufficiently simple that people are
able to state their preferences in response
to the presented choice set.
Another main result is that a simultane-
ous valuation procedure, accounting for in-
teractions between the nonmarket goods
included in cost-benefit analysis for road
investments, significantly reduces the
valuations compared to a separate valua-
tion procedure. In the methodological dis-
cussion of how to value nonmarket goods
for use in cost-benefit analysis, the choice
of valuation context seems, therefore, to be
an important issue.
The institutional differences between
the agencies explain some of the differ-
ences in the agencies work with the plan.
The Public Road Administration has most
resources, largest funding and the longest
experience making them play the leading
role, also independent from their formal
role in heading the planning process.
The process was closely co-ordinated
with the ordinary planning processes in the
agency. The National Rail is next to the
PRA in involvement in the mutual proc-
esses and internal co-ordination of the
work. The National Coastal Administration
has been participating actively in the co-
operation but has fewer resources and plan-
ning skills than the other two. The Civil
Aviation Administration has fewer inter-
ests at stake in the transport planning proc-
ess and has therefore involved them the
least. The planning methods and defini-
tions have probably strengthened the lead-
ing role of the PRA and reduced the posi-
tion of the NCA and the CAA.
Authors: Inger-Anne RavlumSeries: TØI report 488/2000Language: Norwegian with English
summary
Authors: Edvin FrøysadalSeries: TØI working report 1167/
2000Language: Norwegian with English
summary
The co-operation between the four trans-
port agencies to develop a national Trans-
port Plan in Norway, has been concentrated
on the more general transport policy and
less on the means the agencies themselves
have at hand.
The Public Road Administration has most resources, largest funding and the longest experience
making them play the leading role in the planning process.
Comprehensive, common and transparent?The Transport Agencies´ National Transport Planning Process
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 2 7
Annotated reports from the Institute of Transport Economics (TØI), Norway
Foreign visitor surveyare included in the statistics. Altogether
800 000 tourists stayed overnight and
around 380 000 day visitors crossed the
border during this winter season. One-third
of the visitors were on business trips while
the remainder were on holiday. Foreign
tourists spent a total of nearly 4.8 million
guest nights in Norway during the 2000
winter season.
The total number of foreign overnight
guests dropped by six percent compared to
the winter season of the previous year. The
number of holidaymakers declined by
seven percent, whereas a more modest re-
duction was registered for business trips.
The number of foreign guest nights fell by
seven percent and the decline was most
significant among holidaymakers. Foreign
winter traffic to Norway, measured by the
total number of arrivals and guest nights,
is approximately at the same level in 2000
as in 1998.
The number of tourists travelling to
Norway by private motor vehicles or
coaches - who account for four-fifths of
holidaymakers - grew during the 1996 to
1999 winter seasons, but this trend has now
been broken by a decline. The drop in 2000
has been pronounced among visitors from
Sweden and Denmark, who make up the
largest foreign winter holiday markets for
the Norwegian tourism industry.
Road traffic risk in Norway 1997–98
The report presents new estimates of road
traffic risk of road user groups distributed
by age and gender. Exposure data are col-
lected from the National Nor-
wegian Travel Study 1997/98
and annual reports of trans-
port performance in Norway
given by the Institute of
Transport Economics. Acci-
dent data are collected from
the Central Bureau of Statis-
tics (SSB); from the National
Insitute of Public Health
(Folkehelsa) and from annual
reports of road accidents col-
lected by the major Norwe-
gian insurance companies
(TRAST). The results show
that cyclists, motorcyclists and mopedists
are most at risk, both for death and injury,
according to estimates based on SSB-data.
Authors: Jan Vidar Haukeland, ArneRideng
Series: TØI report 485/2000Language: Norwegian with English
summary
Authors: Torkel BjørnskauSeries: TØI report 483/2000Language: Norwegian with English
summary
The report presents the results of the Nor-
wegian foreign visitor survey January -
April 2000. Practically all foreign visitors
One-third of the foreign visitors to
Norway during the winter 2000
were on business trips.
Cyclists in Norway have an
extremely high risk compared
to other road user groups.
Calculations made by use of hospital
data (Folkehelsa) estimate the injury risk
of cyclists to be extremely much larger
than that of other road user groups. The
overall road traffic risk has been fairly sta-
ble during the nineties. The injury risk of
motorcyclists, mopedists and to some ex-
tent pedestrians, has decreased. For car
drivers, car passengers and cyclists, the
risk of injury is unchanged. Injury risk of
young car drivers has, however, increased
during the nineties.
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20002 8
Output-based funding of urban public transport. Model simula-tion of alternative incentives and financial framework
This report studies the possibilities for in-
troducing an alternative funding system
for public transport based on a “Dutch
treat” that involves local authorities and
the central government. Estimates indi-
cate that the central government can ini-
tiate a process that provides huge benefits
relatively easily. This involves subsidies
Productivity growth in the Norwegian ferryindustry 1988–1996Productivity growth in the Norwegian
national roads ferry industry 1988-1996
has been studied with the DEA method.
There are probably errors in official sta-
tistics regarding passengers. Some of our
conclusions are therefore coached in
cautions terms.
There has been zero growth in produc-
tivity with regard to cost efficient pro-
duction of the ferry transport supply.
This is due to a growth in ferry sizes, the
increased capital costs of new ferry
types, and reduced frequencies. The
fixed contract reform of 1990 has prob-
ably contributed to not making it nega-
tive, but this effect has diminished after
a few years. There has been a productiv-
ity growth with regard to the efficient use
of the ferry transport supply to produce
ferry transport services. This is probably
due to the heavy traffic links. Productiv-
ity in the light traffics links may have
declined. There may have been a produc-
tivity decline in the cost efficient produc-
tion of ferry transport services. If so, this
is mainly due to the low demand links,
that vary with passenger numbers.
We have studied the effects of such a
system in Kristianssand, with increased
road user charges of NOK 2 that are ear-
marked for public transport, and central
government funding of NOK 4 for each
new passenger. Additionally, there are
output-based subsidies to the operators.
According to our estimates this will yield
an annual economic benefit of NOK 30m,
and will increase passenger numbers by
20% and reduce rush hour car use by
around 7%.
which are also the links with the highest
relative subsidy levels. The need for sub-
sidies for the industry as a whole may
therefore not have been reduced.
Authors: Kjell Werner Johansen,Bård Norheim
Series: TØI report 484/2000Language: Norwegian with English
summary
Authors: Harald Minken, Marit Killi,Konrad Pütz
Series: TØI report 482/2000Language: Norwegian with English
summary
A subsidy system for the public transport that vary with passenger numbers seems to be
very effective.
Annotated reports from the Institute of Transport Economics (TØI), Norway
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 2 9
Model for transports in Norwegian foreign tradeIn this project TOI has developed a net-
work model for freight transport to and
from Norway. This model has been used
to study six scenarios, each of which il-
lustrates trends or measures that have an
impact on the use of intermodal freight
supply solutions in Norwegian foreign
trade.
These have been compared to a basic
scenario. We have among others calculated
the changes in modal distribution and
transport costs resulting from structural
Speed limits in urban areasThe system for determining speed limits
in urban areas is examined. Studies that
have been made in Norway concerning
Authors: Anne Madslien, GiskeCharlotte Lillehammer, TronEven Skyberg
Series: TØI report 480/2000Language: Norwegian with English
summary
changes in ports and changes in the sup-
ply of sea transport, problems of capacity
in overland transport, changes in the im-
portance attached to the quality of trans-
portation, and increased transport costs for
road transports. In all these cases, both the
amount of general cargo handled by Nor-
wegian ports and the amount crossing the
border at sea have increased.
The effects on air pollution and global
warming depend, however, on whether sea
transport increases its market share at the
expense of rail transport, for which the
emissions are lower than for sea transport
per unit transported, or road transport, for
which the emissions are higher.
Authors: Astrid Amundsen, RuneElvik, Kjartan Sælensminde
Series: TØI report 471/2000Language: Norwegian with English
summary
insecurity are summarised. It has been
found that many parents worry about the
safety of children in traffic.
Estimates of the optimal speed limits on
different types of road in urban areas are
made. Sensitivity analyses are made by
varying input parameters systematically.
Current criteria for setting speed limits are
described. It is concluded that major arte-
rial roads in urban areas can have a higher
speed limit than the general speed limit of
50 km/h. Access roads in residential areas
and streets in shopping areas ought to have
a speed limit of 30 km/h.
Transport performance in Norway 1946–1999In this report, transport performance fig-
ures for the year 1999 are presented to-
gether with other relevant Norwegian
transport statistics. Domestic passenger
transport performance increased by one per
cent in 1999. The public transport sector
experienced high growth rates, while pri-
vate car transport remained at the 1998-
level. The airport express train to and from
Gardermoen was the main reason for a
considerable growth in rail traffic, while
air traffic increased by three per cent. Road
traffic between Norway and abroad rose
by 11 per cent in 1999. Short shopping trips
by Norwegians account for most of this
increase.
Domestic transport of goods increased
by one per cent in 1999. The quantity of
Authors: Arne RidengSeries: TØI report 487/2000Language: Norwegian with English
summary
freight to and from the mainland show only
small changes compared with the level in
1997 and 1998.
Access roads in residential areas and streets in shopping areas ought to have a speed limit of
30 km/h.
Annotated reports from the Institute of Transport Economics (TØI), Norway
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20003 0
Annotated reports from the Swedish National Road and Transport Research Institute
Authors: Marieke H. MartensSeries: KFB & VTI forskning/re-
search 35ALanguage: English
Automatic information processing (AVIP)
in traffic refers to a driver state, in which
expectations have replaced a large part of
the active information intake exerted by a
highly attentive driver. Instead of actively
scanning the visual environment, the driver
only passively monitors the outside world,
requiring little attention.
The current report provides an overview
of several theoretical approaches that are
valuable when discussing the phenomenon
of automatic visual information process-
ing. The theoretical approaches that are
discussed are automatic performance, ex-
pectation approaches, signal detection
theory, visual search approaches and vigi-
lance research.
Besides a discussion of these theoreti-
cal approaches, different methods for
measuring attention, expectations or visual
information processing are discussed, all
with their advantages and their limitations.
The various methods that are described
are physiological measures (with most
promising results for measures dealing
with the central nervous system), spare
capacity measures (with the danger of in-
terfering with the automatic processing),
Automatic visual information processing and expectationsin Traffic eye movement measures (not being able to
distinguish between what one looks at and
what one perceives), verbal reports (not be-
ing able to find automatic processes) and
recording driving behaviour (with the dif-
ficult link between provided information
and the actual response).
Since all measures have their specific
limitations, combining these measures is
essential since they complement one an-
other. Although a lot of research touches
the subject of automatic visual information
processing and expectations in traffic,
many interesting research questions re-
main unanswered, leaving open a large
area for research.
Effects of tunnel wall pattern on simulated driving behaviour
The VTI researcher Jan Törnros has com-
pared speed reducing effects of various
wall or ceiling patterns in road tunnels.
The study was carried through in a driv-
ing simulator. 24 subjects (12 men, 12
women), aged 24–54, participated in a re-
peated measurements design.
Six patterns were compared with an
unpatterned tunnel as a control condition.
Behavioural effect measures were speed,
lateral position, position of gas pedal re-
lease, position of retardation initiation and
of maximal retardation, and maximal re-
tardation. It was also studied whether ac-
cess to speedometer readings would have
any effects.
It was found that wall and ceiling pat-
terns that preceded the curve did not show
any effects on speed choice. Only an ef-
fect of the tunnel tube was demonstrated.
Nor did lateral position variation differ
between patterns. Only the tunnel tube
was shown to have an effect.
Whether subjects had access to speed-
ometer readings or not, did not influence
any of the comparisons.
Subjective effects were also analysed.
The answers given by the subjects do not
seem to favour any particular pattern over
any other, even if there was a tendency
that the unpatterned condition and the
condition with a narrow ceiling pattern
were regarded to cause more sensations of
unpleasantness. A majority of the subjects
indicated that the patterns had a speed re-
ducing effect with a narrow wall pattern
and narrow wall/ceiling pattern receiving
a few more votes than other pattern con-
ditions - a result that was not confirmed
by the behavioural analyses.
Authors: Jan TörnrosSeries: VTI EC Research 9Language: English
PHOTO: STAFFAN GUSTAVSSON, REDAKTA
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 2000 3 1
Annotated reports from the Swedish National Road and Transport Research Institute
Dynamic vehicle reactions on the Ruch type of S-shapedsuperelevation rampsThis paper, presented at the international
railway conference Comprail -2000 in
Bologna, reports an applied study based
on principles derived in VTI rapport 420A,
421A and 424A.
The S-shaped superelevation ramps
have been believed to result in more fa-
vourable vehicle reactions than ramps
where superelevation and curvature
change linearly (with respect to longitudi-
nal distance). These ideas were tested al-
ready during 1998 and results were re-
ported in VTI Särtryck 318. In the study
from 1998, no substantial advantages were
found with the S-shaped ramps.
The specific aspect of the present study
is whether the horizontal curvature of the
track should be related to the rails or to a
level above the rails, i.e. the height of the
mass centre of the entire vehicle or the
wheelsets.
Vehicle reactions have been simulated
with the multibody computer code
GENSYS and evaluated according to draft
standards from the CEN and the UIC. Ve-
hicle models for the Eurofima standard
coach (UIC Z1) and the X2000 tilting
trainset have been used.
The results indicate that vertical track
forces are almost independent of the height
of the path of the horizontal alignment,
while lateral track forces are sometimes
slightly worse and sometimes slightly bet-
ter with S-shaped ramps than linear ramps.
Passenger comfort is not significantly im-
proved with the S-shaped ramps.
The most important conclusion from the
present study is that it cannot be proved
that S-shaped ramps can be used as sub-
stitutes for linear ramps with sufficient
lengths for high speed traffic. The main
task in track design is to find optimal com-
binations of curve radii and lengths of tra-
ditional linear superelevation ramps and
corresponding type of transition curves.
Authors: Björn KufverSeries: Computers in Railways VII.
Southampton: WIT Press,pp663-672.
Language: English
This publication is to be seen both as an
overall description of a specific freight
transport forecasting system and as an in-
troduction to most of the other publica-
tions on the subject “Transport demand
of the economy” of which this publica-
tion is a part.
The aim of the freight transport fore-
casting system is to provide an overall,
and as far as possible consistent, descrip-
tion of the demand for freight transport in
Sweden and between Sweden and other
countries.
The model is based on a base year with
known freight transport flows and a
known description of the economy and the
development of the economy up to the
forecast year. For the description of the
goods flows of the base year, data are
needed regarding the transport pattern (to/
from relationships), disaggregated into
mode and type of product. Economic
growth is measured in terms of produc-
tion, consumption, final use, import and
export. All variables are disaggregated
into type of industry. The forecasting
model also needs other economic statis-
tics such as employment per type of busi-
ness and region, and values of goods for
the base year and forecast year.
Obviously, the development of the
economy in future is unknown; it will vary
depending on a large number of factors.
The model system therefore makes “con-
ditional forecasts”. This means that differ-
ent future scenarios are constructed to deal
with this uncertainty. By defining differ-
ent alternative courses of development,
VTI/TPR-model – A forecasting system for freight transport
which are based on reasonable assump-
tions, alternative forecasts are obtained.
Finally, the software and its user inter-
face are presented.
Authors: Jan R. ErikssonSeries: KFB & VTI forskning/re-
search 31Language: Swedish with an English
summary
PHOTO: CHRISTER TONSTRÖM, MEDIABILD
NORDIC ROAD & TRANSPORT RESEARCH NO. 3 · 20003 2
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REQUESTS FOR BACK ISSUES, AND NOTIFICATION OF ADDRESS CHANGES:Readers outside the Nordic countries: see Swedish address.Readers in the Nordic countries: see addresses below.
Web site: www.vti.se/nordic
Helen Hasz-SinghDanish Road InstituteP.O. Box 235DK-4000 RoskildePhone: + 45 46 30 70 00Fax: + 45 46 30 71 05E-mail: [email protected]
Harald AasInstitute of Transport Economics (TØI)P.O. Box 6110 EtterstadN-0602 OsloPhone: + 47 22 57 38 00Fax: + 47 22 57 02 90Order phone: + 47 22 57 39 13E-mail: [email protected]
Kari MäkeläVTT, Communities and InfrastructureP.O. Box 1901FIN-02044 VTTPhone: + 358 9 45 64 586Fax: + 358 9 46 41 74E-mail: [email protected]
Helge HolteNorwegian Public Roads Administra-tionP.O. Box 8142 Dep.N-0033 OsloPhone: + 47 22 07 39 00Fax: + 47 22 07 34 44E-mail: [email protected]
Hreinn HaraldssonPublic Roads AdministrationBorgartún 7IS-105 ReykjavikPhone: + 354 563 1400Fax: + 354 562 2332E-mail: [email protected]
Sigvard TimSwedish National Road andTransport Research Institute (VTI)SE-581 95 LinköpingPhone: + 46 13 20 40 00Fax: + 46 13 14 14 36Order phone: + 46 13 20 42 24E-mail: [email protected]
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