Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
DESIGNFOR
DURABILITY
FACULTY OF ENGINEERING & INFORMATION TECHNOLOGY
UNIVERSITY OF TECHNOLOGY SYDNEY
TABLE OF CONTENT
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
1. Introduction…………………………………………………………........
5
2. Structural Members…………………………………………………........
5
2.1Substructure and Foundations…………….…………………………..
5
2.1.1Pile…………………………………………………………........ 5
2.1.2Headstock…………………….........…………………………… 6
2.2 Superstructure...................................................................................... 6
2.2.1Abutment……………………………………………………….. 6
2.2.2Pier…………………………………………………………....... 7
2.2.3Concrete Planks………………………………………………… 7
2.2.4Concrete Deck………………………………………….......…... 8
2.2.5Barriers………………………………………………………..... 8
3. Construction Process…………………………………….….…..………. 9
4. Environmental loads…………………………………………..………...10
4.1Analytical Results………………………………............................... 11
4.2Carbonation …………………………………………........….……...
11
4.3Sulphate induces corrosion …………………………..…….………. 13
4.4Surface chloride …………………………………….……………… 13
4.5Airborne chloride…………………………………..………………..
15
4.6ASR (alkali silica reactivity) ………………………………………..
15
4.6.1 Structure Classification………...........………………..............
20
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
4.6.2 Level of Precaution Definition ………...........………………..
21
4.6.3 Aggregate Reactivity Classification ………...........…………..
21
4.6.4 Aggregate Suggestion ………...........………………...............
21
4.6.5 Risk Reduction ………...........………………...........………...
22
5. Cathodic Protection ………...........………………...........…………......
23
6. Specification ………...........………………...........……….……….........
24
6.1Performance Specification………...........………………...........
………................. 25
6.1.1 Diffusion coefficient................................................................
24
6.1.2 Volume of Permeability. .........................................................
24
6.1.3 Sorptivity. .................................................................................25
6.1.4 Rapid Ion Permeability.............................................................
26
6.2 Prescriptive base specification...........................................................
27
6.2.1 Cover quantity.......................................................................... 27
6.2.2 Quality of concrete .................................................................. 28
6.2.3 Type of cement ........................................................................ 28
6.2.4 Use of SCM. .............................................................................28
6.2.5 Type of aggregate .................................................................... 28
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
6.2.6 Moisture penetration.................................................................
29
6.2.7 Additional protective measure APM........................................ 29
6.2.8 Casting and Curing ...................................................................
29
6.2.9 Service life inspection...............................................................
29
7. Reference................................................................................................. 31
LIST OF FIGURES
Figure 1. Pile…………………………………………….....……………………
6
Figure 2. Headstock……………………………………..………………………
7
Figure3. Abutment………………………………………………………………
7
Figure 4. Pier…………………………………………...………………………. 8
Figure 5. Concrete Planks……………………….......…………………………..
8
Figure 6. Concrete Deck……………………………………..………………….
9
Figure 7. Barrier……………………………………………………………...... 9
Figure 8 Local Cell Corrosion........................................................................... 23
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
Figure 9 Principal of cathodic corrosion protection …………………………...
23
Figure10 Diffusion coefficient D365 .………………….................................. 24
Figure 11 Diffusion coefficient D28.................................................................. 24
Figure 11. Sorptivity……………………………………......................…….....
24
Figure 12. Properties of SCMs……………………………..............……….....
25
Figure 13. Aggregate Reactivity……………………………………................ 25
Figure 14. Potential reactivity of different aggregate........................................ 26
LIST OF TABLES
Table 1. Environmental Loads………………………..........……………….... 11
Table 2. Analytical Results …………………….…………………................. 12
Table 3. Correction Factors……………………………………….................. 13
Table 4. Carbonation Coefficients………………………………………........ 13
Table 5. Results……………………………………….................................... 13
Table 6: ACEC Classification ……………………......................................... 14
Table 7: DC classifications............................................................................... 15
Table 8: In situ concrete.................................................................................... 15
Table 9: Pre-cast concrete................................................................................. 16
Table 10: Diffusion coefficients of concrete in tidal areas..................................
17
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
1. Introduction
Durability of a structure describes qualitatively the ability of a structure and its component to
perform the functions for which they have been designed, over a specified period of time,
when exposed to their environment. Cracking in a structure leads to exposing of
reinforcement steel which undergoes corrosion. We prepared a durability report of imaginary
highway twin bridges for design life of 100 years. The bridge is located near Ballina which is
736 km by road from Sydney.
2. Structural Components
The structural components of bridge are placed under the two sections:
Substructure or Foundations
Superstructure
2.1 Substructure or Foundations
The structural part below the ground is called substructure. Foundation is important structural
part of the bridge. The main role of foundation is to bear the load of all the members above it.
This includes:
2.1.1 Pile:
The piles used at the construction site are precast piles which transfers the load from
headstock to the ground. The piles are octagonally shaped at the bridge site.
Fig.1 Pile
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
2.1.2 Headstock:
It is the structural component which is rests on the pile.
Fig.2 Headstock
2.2 Superstructure
The structural part above the ground is called superstructure. The structural components that
are classified under this section are:
2.2.1 Abutment:
Fig.3 Abutment
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
2.2.2 Pier
It is the structural component which rests above the headstock. The height of the pier
headstock is 1400 mm.
Fig.4 Pier
2.2.3 Concrete Planks:
Precast prestressed concrete planks are used at the construction site. 300 mm diameter void is
provided at the centre of it. Height of concrete plank is 600 mm. Bearing strips are provided
between the pier headstock and concrete plank layer.
Fig.5 Concrete Planks
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
2.2.4 Concrete Deck:
180 mm thick concrete deck slab is provided on the precast prestressed concrete planks. 75
mm thick bituminous surfacing is done on the concrete deck
Fig.6 Concrete Deck
2.2.5 Barriers:
Precast barriers are used at the construction site which is provided on the concrete deck.
Fig.7 Barrier
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
3. Construction process
The construction of the twin bridge system will include two way of construction:
Pre-cast-rigid formwork; used to achieve certain mechanical properties of the
concrete elements. This method allows to have better concrete elements with a higher
resistance to external attack and longer durability.
In-situ- general formwork; used to cast the element that cannot be pre-casted.
The following procedure will be adopted to construct the twin bridges:
1. The piles will be pre-cast off-site and transported to the site before being
mechanically driven into the ground;
2. The formwork for the abutments are to be placed on the piles, and the abutments are
to be cast in-situ;
3. Headstock/pier formwork have to be constructed above the piles, and members need
to be casted in-situ;
4. Pre-cast concrete planks are to be transported to site and placed across the spans
between the piers;
5. Install 18mm fibre cement sheeting between concrete planks;
6. The pre-casted deck sections are transported in the construction site, lifted and lay
down up to the planks;
7. Pre-cast barriers are installed;
8. The asphalt is applied on the surface.
Precautions must be taken to prevent any cracking or damage to the pre-cast members
during the transportation on site.
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
4. Environmental Loads
In the comparison of all the environmental loads present both above ground and below
ground, it has been concluded that carbonation and chloride-induced corrosion will cause
most damage to the structural members. Another corrosion mechanism that may affect the
structure is the Alkali Silica Reaction, which will be most critical in the concrete planks,
which do not experience any wetting or drying and are exposed to the atmosphere.
Structural member Exposure
Classification
(AS3600, AS5100)
Environmental Loads Construction
Technique
Piles C2 (Tidal/splash
zone)
Carbonation
Sulphate
Surface Chloride
Pre-cast, driven
Abutments B2 (Coastal) Carbonation
sulphate
airborne chloride
Cast in-situ
Piers C1 (spray zone) Carbonation
Airborne chloride
In-situ
Concrete Planks B2 (Coastal) Carbonation
Airborne Chloride
Pre-cast
Deck B2 (Coastal) Minimal
carbonation
Pre-cast
Barriers B2 (Coastal) Carbonation Pre-cast
Table 1: Environmental loads
4.1 Analytical Results
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
Table 2: Analytical Results
4.2 Carbonation
Carbonation has a major effect on most of the structural members of the twin bridge system
as most members are exposed to the atmosphere and CO2. The deck is protected by an 75mm
asphalt layer on top and concrete planks and 18mm fibre cement sheeting below, therefore it
will only experience a minimal amount of carbonation, if any at all.
Measures to mitigate carbonation that can be controlled include:
Cement type;
Water/cement ratio;
Curing (Degree of Hydration);
Compaction;
Cracking.
These factors are controlled effectively through the pre-cast process where the concrete
members are cast and cured in a controlled environment, increasing the mechanical properties
of the concrete. For the in-situ members, formwork is to remain for a minimum of 7 days
after casting to control crack development.
To determine the depth of carbonation, the following equation is used:
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Location Depth(m) pH
Moisture Content
(%)
Sulphate
(SO42)
(mg/kg)
Chloride(CL)
(mg/kg)BH - Abut A SB 8.50 8.1 24.8 670 2,360BH - Pier 2 SB 7.00 7.8 23.8 1,000 1,670BH - Abut A NB 1.00 8.2 16.5 50 200BH - Pier 1 NB 8.50 7.4 21.2 15,600 2,280BH - Pier 2 NB 1.00 8.1 23.4 1,000 1,560BH - Abut B SB 2.50 7.5 18.0 90 700
Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
Dc = K x t0.5
Dc- Depth of carbonation
K- carbonation coefficient
t- time (i.e. 100 years)
the following tables are used to determine the carbonation coefficient and correction factors
for each structural member. All members will consist of a compressive strength >35 MPa and
have fly ash content between 30-40%.
Table 3: Carbonation Coefficients
Member(s) Carbonation
Coefficient
Correction Factor Depth of
Carbonation
Piles, piers,
abutments, barriers
1 1.10 11.0mm
Planks 2.5 1.10 27.5mm
Table 5: Results
The engineering drawings provided allow for a minimum concrete cover:
50mm piles
45mm for abutment areas in atmospheric exposure,
60mm for abutments areas in contact with the ground
70mm for the piers
30mm for the barriers, therefore all structural members have adequate cover in terms
of carbonation.
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Table 4: Correction Factor
Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
4.3 Sulphate-induce Corrosion
The highest sulphate value has been found at the BH-PIER 1 NB, 8.50m.
SULPHATE=15600 mg/Kg
The Sulphate classification and analysis has been done through the BRE method.
Based on the Aggressive Chemical Environment for Concrete Table (ACEC), considering the
sulphate value converted in mg/l and the pH value equal to 7.4 is possible to define the
Design Sulphate Class for location as:
DS-5 AC-4s
After that the class for location has been determined, and based on 100 years working life is
possible define the specification of concrete and additional protective measure (APM)
through the following table.
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Table 6:ACEC Classification
Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
4.3.1 Cast in situ
The table 8 are for concrete cast-in-situ, while the figure 9 if for precast concrete products.
For table 7 for elements cast in situ, the DC class and the APMs are suggested as:
DC-4+APM3f
For this classification the BRE suggest two type of APM that are coatings and water resisting
barrier. We will adopt:
COATINGS
The BRE gives also the indication for the W/C ratio, aggregate size and type of cement.
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Table 7: DC classifications
Table 8: In situ concrete
Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
Where the the cement suggested for a water/ ratio= 0.35 is:
CEMII/B-V+SR; Portland cement with addition of fly ash (FA) content should be not less
than 25% of the total cement content.
4.3.2 Precast
Form the precast table the come out with the same result.
CEMII/B-V+SR; Portland cement with addition of fly ash (FA) content should be not less
than 25% of the total cement content.
In addition, in the highly chloride rich environment, the sulphate ions are mitigated and any
sulphate attack will be delayed by the chloride ions.
4.4 Surface Chlorides
To determine the effect surface chlorides, have on the steel reinforced concrete, we must
determine the chloride concentration at the depth of the steel reinforcement. This
concentration is then to be compared to the critical chloride threshold level, which is
determined by the type of cement, use of SCM’s, compressive strength and weight/binder
ratio of the mix. This calculation is to be conducted at the most critical area of the structural
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Table 9: Precast concrete
Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
members, which has been determined to be the area on the piles that is exposed to the tidal
zone where there is a constant change in relative humidity and the adverse effect of wetting
and drying.
Using the table below we can determine the weight/binder ratio, chloride concentration at the
surface (Cs), alpha (α), diffusion coefficient after 1 year (D1) and the critical chloride content
for the type of cement mix used. As described above in ‘Carbonation’, a compressive strength
of >35mPa and fly ash content of 30-40% will be used. The nominated concrete cover value
at the piles is 50mm and this will be used as the piles are the most susceptible structural
member to surface chloride attack.
Table 10: Diffusion coefficients of concrete in tidal areas
The highlighted line shows the required figures, which can be used in the following
equations:
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
Convert 100 years into seconds for the equation:
Then use the chloride concentration equation with the calculated values:
The critical chloride content, or the chloride threshold, as taken from the table above, is 0.05.
the calculated chloride concentration is below this, hence the concrete cover is adequate for
protecting the structure against surface chloride attack for the 100-year design life.
4.5 Airborne Chlorides
The twin bridges are to be designed to be within 1km of the coast, which will allow for
airborne chlorides to affect the bridge. Unfortunately, there is no procedure to determine the
exact concentration of airborne chlorides at any location. It is however known that surface
chlorides have a greater effect on reinforced concrete structures than airborne chlorides, and
as the concrete cover is adequate for the former, we can assume the structural members will
also be adequately protected from airborne chlorides
4.6 ASR-Alkali silica reactivity
The alkali silica reactivity has been considered has the most dangerous cause that can affect and reduce the service life of the bridge structure.
Based on the HB 79:2015 will be discuss and provide a guidance to contrast and minimising the alkali silica reactivity in order to guarantee the service life of the structure.
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
4.6.1 Structure Classification
For the table 1.1 in figure 11, the structure classification based on ASR damage
acceptance is;
S2
‘‘Minor ASR damage is acceptable of manageable’’
For table 1.2 in figure 9, the classification of the structure by the impact of the
environment on the likelihood of ASR is;
E3
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Figure 11: Classification of structure by the consequence and acceptability of ASR damage.
Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
4.6.2 Level of Precaution Definition
Based on the information acquired above, using the table in figure12 it is possible to define
the level of precaution needed to the minimise the damage due to ASR reaction.
Figure 12: Level of precaution required.
The level of precaution necessary for the structure to perform for the whole design life is
STANDARD. This means that the risk of damage due to the ASR attack is very low, despite
the aggravating condition.
4.6.3 Aggregate reactivity classification
As the AS1141.60.1 suggest, the aggregates to be slowly reactive must have E (mortar bar
expansion) equal to 0.10a after 21 days. Therefore, the aggregates used in this mix design
have:
E=0.10a
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Figure 9: Impact of the environment.
Figure 13: Aggregate reactivity .
Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
With a prism expansion less than 0.03% after 52 weeks.
4.6.4 Aggregates suggestion
The aggregates play a fundamental role in the ASR. For this reason, the choice of the
adequate aggregate is the main action that should be taken to mitigate the ASR and reduce he
risk of concrete damage. According to the HB 79, the classification for the level of
Precaution is STANDARD. Thus, for the figure 14 select the type of aggregate as:
SLOWLY REACTIVE.
From the the lecture give by Mr Peter Clark, it is possible to select a non or slowly reactive aggregate. Figure 15
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Figure 14. Risk of concrete damage due to ASR.
Figure 15. Potential reactivity of different aggregate.
Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
The road authority of New South Wales in order to have a further control on the aggregates,
has adopted an extra specification.
All aggregate need to be assessed for AAR using AMBT method. Annually test.
Aggregate classified as non-reactive ma be used without mitigative measures.
Aggregate assessed as slow reactive may be used with the addition of 25% fly ash.
Where aggregates are assessed as reactive the specification recommendation is to used an
alternative aggregate, or an alternative mitigate proposal.
4.6.5 Risk Reduction
To reduce the risk of damage, the total Alkali content must be less than 2.8kg/m3. It is
determinate by the sum of content in:
A = Ac +B+H+W+D
Where;
A= Total alkali content of the concrete mix
Ac=Total alkali content of Portland cement
B = Total alkali content of SCM admixture
H = Reactive alkali contribution for NaCl in aggregate
W = Total alkali contribution from mixing water
D = Total alkali contribution from chemical admixtures and pigments
The high quantity of alkali is present in cement. The Type GP cement produced in Australia
has an alkali content between 0.5 to 0.6%. Therefore, to reduce the risk of the ASR is
necessary to reduce the amount of cement content into the concrete mix. HB79 suggests to
replace the cement content with SCMs as Fly Ash and Slag.
Fly Ash: 25% of it is sufficient to mitigate ASR. It can also be increase up to 40%
(low calcium ash) for highly critical structures with a long design life.
Slag: between 50 to 65% is sufficient to mitigate the ASR risk.
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
5. Cathodic Protection
It is a technique which is used to control the corrosion of metal surface by making it cathode of an electrochemical cell. The corrosion current is driven away be the cathodic protection current. The anode site transformed in cathodic, with a new anode system. The steel potential moves negative and the chlorides migrate away from steel (to anode).
Figure 8 Local Cell Corrosion Figure 9 Principle 0f cathodic corrosion protection
To ensure the service life of the reinforced and prestressed components, taking into account that:
Exposure classification is B2 Characteristic strength: 50 MPa Use minimum cover of 40 mm
Cathodic Protection is adopted for Pier Headstock and Abutment.
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Figure 16 Properties of SCMs
Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
For these elements, we decide to use the Cathodic Prevention (CPrev). Therefore, the cathodic protection is applied to the structures during the construction process, in order to reduce the costs and have a less laborious process in the future.
There are number of ways to do cathodic protection which are as follows. For this project we adopt the:
Sacrificial Anode
The reinforcement is connected to the negative terminal of power that supply and then apply current.
6. Specifications
6.1 Performance-based specifications
The following performance-based specifications will be used to ensure the durability
requirements of the twin bridge system are met.
6.1.1 Diffusion Coefficient
The diffusion coefficient De.365 is equal to 1x10-12m2/sec as determined from the
following graph for GB1 and 0.4% water/cement ratio:
Chloride diffusion
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Figure 10 Diffusion coefficient D365
Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
The diffusion coefficient D28 is equal to 3x10-12m2/sec for GB cement as determined from the
following table:
6.1.2 Volume of
Permeability
6.1.2 Volume of permeable voids (VPV) is 13.1%, determined from the following table
using the value for D365 = 2x10-12m2/sec:
6.1.3 Sorptivity
Sorptivity value of 14mm from the following graph:
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Figure 11 Diffusion coefficient D28
Figure 12, Sorptivity.
Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
6.1.4 Rapid Ion Permeability
Rapid Ion penetrability (RCIP) is 1000 Coulomb:
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
Specification Value
Compressive strength 50 Mpa
De.365 1x10-12m2/sec
D28 3x10-12m2/sec
VPV 13.1%
RCIP 1000 Coulomb
Sorptivity 14mm
To ensure the concrete delivered is to the standard and specification outlined, standard slump
tests will be performed as soon as it is delivered. A conservative value of 5% defective
concrete will be adopted.
Figure 1: Comparative Performance Table
6.2 Prescriptive base specification
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
6.2.1 Cover quantity:
Cover plays a fundamental role in the long-term structure performance. It guaranties a
protection against corrosion, protection against the aggressive external factors as: chloride,
sulfate and carbonation.
The time to corrosion initiation t, is strongly dependent to the cover quantity. It is a function
of square of cover x. Therefore, if 10% of cover thickness is lost there is a 19 % of service
life reduction.
According to RMS B80 clause 8.4 a control of cover is required before and after the
placement of concrete.
Pre-pour control: Is required a control to check is the distance between the steel
reinforcement and the formwork are respected as designed.
Post-pour control: A control of cover thickness by a cover meter is required after that
the concrete has been placed, to verify if the value specified is respected as designed.
6.2.2 Quality of concrete
The control of concrete quality is important to ensure the performance life of
the structure. If 10% reduction in quality correspond to 10% reduction is service
life. Therefore, in order to ensure the quality of it, 5% of defective level is
adopted.
6.2.3 Type of cement:
Type GBII, Low-alkali cement. GP with Na2O equiv non more than 0.6% and the addition of
SCMs.
6.2.4 Use of SCMs:
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
Elements Exposure
classification
Types
of
SCMs
% cement
material
content
rang
(kg/m3)
Maximum
water/cement
ratio
Piles C2 Fly Ash 25% 420-550 0.35
Headstock B2 Fly Ash 25% 370-600 0.40
Abutments B2 Fly Ash 25% 370-600 0.40
Piers C1 Blende
d
Minimum
65% BFS
420-600 0.40
Concrete
plank
B2 Blende
d
25% FA,
50% GP,
25% Slag
370-600 0.40
Concrete
deck
B2 Blende
d
25% FA,
50% GP,
25% Slag
370-600 0.40
Barriers B2 Blende
d
25% FA,
50% GP,
25% Slag
370-600 0.40
Figure 16 Use of SCMs
6.2.5 Type of aggregate:
They must be SLOWLY REACTIVE aggregate.
6.2.6 Moisture prevention:
The structure should be designed to avoid as much as possible any ponding. A maintenance
program should be stablished to keep the structure joint sealed and the cracks grouted to try
to avoid the moisture ingress.
6.2.7 Additional protective measure APM
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
Coating: The coating must be applied on the pier section in order to protect it against the
sulphate.
Cathodic protection: Cathodic protection must be applied to Pier Headstocks and
Abutments during the construction phase.
6.2.8 Casting and Curing
In order to reduce and control the cracks the casting and curing must be controlled.
Casting:
For the member casted in situ the formwork need to be kept for a minimum of
7 days after casting. While, for the pre-cast members, they must be casted in
rigid formwork and with high vibration.
Curing:
For the Headstock, Abutments and Piers, a wet curing to trowel finished
surfaces is required in accord to the AS3799
For Barriers, Planks and Piles, a low pressure and accelerate steam curing is
adopted according to the AS1597.2
6.2.9 Service life inspections
In order to check and ensure the service and the performance life of the bridge, a
periodical inspection between 6 and 10 years is required.
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
7. References:
Sirivivatnanon, V. and Cao, H.T., "The need for and a method to control concrete cover", Proceedings of the Second International RILEM/CEB Symposium on Quality Control of Concrete Structures, Belgium, June 1991.
Standards Australia 2004, Australian Standard AS 5100.5: Bridge design – Part 5: Concrete, Standards Australia, Sydney.Standards Australia 2008, Australian Standard AS 5100.5 Supplement 1: Bridge design – Concrete – Commentary (Supplement to AS 5100.5 – 2004), Standards Australia, Sydney
HB 79:2015 Handbook, “Alkali Aggregate Reaction- Guidelines on Minimising the Risk of
damage to Concrete Structures in Australia.
BRE brepress Construction division, Concrete in Agressive Ground. SD1: 2005
Standards Australia 2009, Concrete Structure, AS 3600-2009, Standards Australia, Sydney.
Sirivivatnanon, V. 2016, '11 Cathodic protection & other electrochemical methods’, UTS
Online Subject 42907, lecture notes, UTS, Sydney, 13 August 2016.
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Design for Durability Deepanshu Patel 12838607 Giorgio Schievenin 12696074 Will Davis 12049262
Sirivivatnanon, V. 2016, '10 QC of Concrete Cover & Abrasion Resistance', UTS Online
Subject 42907, lecture notes, UTS, Sydney, viewed 10 August 2016.
Sirivivatnanon, V. 2016, '7 Alkali Silica Reaction (ASR)', UTS Online Subject 42907, lecture
notes, UTS, Sydney, viewed 7 August 2016. Sirivivatnanon, V. 2016, '6 Corrosion of
Concrete', UTS Online Subject 42907, lecture notes, UTS, Sydney, viewed 5 August 2016.
Sirivivatnanon, V. 2016, '5 Chloride-induced Corrosion', UTS Online Subject 42907, lecture
notes, UTS, Sydney, viewed 1 August 2016.
Sirivivatnanon, V. 2016, '4 Carbonation-induced Corrosion', UTS Online Subject 42907,
lecture notes, UTS, Sydney, viewed 1 August 2016.
Sirivivatnanon, V. 2016, '2 Environmental loads', UTS Online Subject 42907, lecture notes,
UTS, Sydney, viewed 1 August 2016.
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