testing of concrete sleepers and fastener systems for … · shoulder/fastening system wear or...
TRANSCRIPT
Justin Grassé, David Lange
Presenter: Marcus Dersch
10th International Heavy Haul Association Conference
New Delhi, India
6 February 2013
Testing of Concrete Sleepers and Fastener Systems
for the Understanding of Mechanistic Behavior
Slide 2 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Outline • Background
• UIUC Concrete Sleeper Research
Overview
• Objectives of Field Research
• Field Instrumentation Strategy
• Testing at Transportation Technology
Center (TTC)
– Pueblo, CO, USA
• Experimental Results
• Findings
• Future Work
Slide 3 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Fastening System Components
Rail Pad
Assembly
Clip
Insulator
Concrete Crosstie
Shoulder
Rail
Slide 4 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
2012 International Survey Results Criticality of Problems – North American Responses
Failure Mode Average Rank
Deterioration of concrete material beneath the rail 6.43
Shoulder/fastening system wear or fatigue 6.38
Cracking from dynamic loads 4.83
Derailment damage 4.57
Cracking from center binding 4.50
Tamping damage 4.14
Other (e.g. manufactured defect) 3.57
Cracking from environmental/chemical degradation 3.50
Research Topic Average Rank
Prevention or repair of rail seat deterioration 3.60
Fastening system design 3.60
Materials design 3.00
Optimize crosstie design 2.80
Track system design 2.00
Slide 5 Railway Engineering and UIUC Research Overview
Research Levels (and Examples)
Materials
Concrete Mix Design
Rail Seat Surface
Treatments
Pad / Insulator Materials
Components
Fastener Yield Stress
Insulator Post Compression
Concrete Prestress
Design
System
Finite Element Modeling
Full-Scale Laboratory
Experimentation
Field Experimentation
Slide 6 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Research Sponsors and
Projects • CN Fellowship in Rail Engineering (RSD)
• Association of American Railroads (AAR)
Technology Scanning Program (RSD and
Fastening System Wear and Fatigue)
• Amsted RPS / Amsted Rail, Inc.
(Fastening System Wear and Fatigue)
• NEXTRANS Region 5 Transportation
Center (RSD)
• Federal Railroad Administration (FRA)
(Fastening System Wear and Fatigue,
Cracking, Environmental, etc.)
• National University Rail (NURail)
(Fastening System Wear and Fatigue)
National University Rail Center
Slide 7 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Comprehensive
Literature Review
International Tie and
Fastening System Survey
Loading Regime (Input)
Study
Rail Seat Load
Calculation
Methodologies
Involvement of Industry
Experts
Comprehensive
Literature Review
International Tie and
Fastening System Survey
Loading Regime (Input)
Study
Rail Seat Load
Calculation
Methodologies
Involvement of Industry
Experts
Data Collection
Document Depository
Groundwork for
Mechanistic Design
International Survey Report
Load Path Map
Parametric Analysis
State of Practice Report
Validated Tie and
Fastening System Model
Data Collection
Document Depository
Groundwork for
Mechanistic Design
International Survey Report
Load Path Map
Parametric Analysis
State of Practice Report
Validated Tie and
Fastening System Model
Laboratory
Study
Modeling
Field
Study
Impro
ved R
ecom
mend
ed P
ractic
es
Laboratory
Study
FRA Tie and Fastener Project Structure
Inputs Outputs/Deliverables
Slide 8 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
• Lay groundwork for mechanistic design of concrete
sleepers and elastic fasteners
• Quantify the demands placed on each component within
the system
• Develop an understanding into field loading conditions
• Provide insight for future field testing
• Collect data to validate the UIUC concrete sleeper and
fastening system FE model
Goals of Field Instrumentation
Slide 9 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Areas of Investigation Fasteners/ Insulator
• Strain of fasteners
• Stresses on insulator
• Moments at the
rail seat
• Stresses at rail seat
• Vertical
displacements of
sleepers
Concrete Sleepers
Rail
• Stresses at rail seat
• Strains in the web
• Displacements of web/base
Slide 10 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
2012 Field Instrumentation Map • Full Instrumentation
– Lateral, vertical, and chevron strain gauges on rail
– Embedment and external concrete strain gauges on crosstie
– Matrix based tactile surface sensors at rail seat (at rail seat W)
– Linear potentiometers on rail and crosstie
• Partial Instrumentation
– Vertical strain gauges on rail
– Matrix based tactile surface sensors (at rail seats G and Y)
– Linear potentiometers on crosstie (at rail seats C and G)
Slide 11 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Field Instrumentation Locations
• TTC (Pueblo, CO, USA)
• High Tonnage Loop (HTL)
– Curve (~5°)
– Safelok I Fasteners
Slide 12 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Field Instrumentation Locations
• TTC (Pueblo, CO, USA)
• Railroad Test Track (RTT)
– Tangent
– Safelok I Fasteners
Slide 13 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Loading Environment
• Track Loading Vehicle (TLV)
– Static
– Dynamic
• Freight Consist
– 6-axle locomotive
• 30t axles (393 GRL)
– Instrumented car
– Nine cars
• 30, 33, and 36t axles
(263, 286, 315 GRL cars)
• Passenger Consist
– 4-axle locomotive
• 29t axles (255 GRL)
– Nine coaches
• 10t axles (87 GRL cars)
Slide 14 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Fully Instrumented Rail Seats
Instrumented
Low Rail
Slide 15 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Instrumented Low Rail
Slide 16 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Field-side Instrumentation
Vertical Sleeper
Displacement
Base Displacement
Vertical Web
Strain
Clip Strain
Slide 17 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Gauge-side Instrumentation
Lateral Rail
Displacement
Slide 18 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Data Acquisition System
Slide 19 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
0
2
4
6
8
10
12
14
16
18
0
10
20
30
40
50
60
70
80
24 (15) 48 (30) 66 (45) 97 (60)
Late
ral Load (
kip
s)
Late
ral Load (
kN
)
Train Speed, km/h (mph)
Lateral Loads Acting on a Tangent Track
Lateral
Loads
Max
Median Lower quartile
Upper quartile
Leading axles of a 10-car freight
train (30, 33, and 36t axle loads).
Minimum
Left Right
Tangent
Slide 20 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
0
2
4
6
8
10
12
14
16
18
0
10
20
30
40
50
60
70
80
24 (15) 48 (30) 66 (45) 97 (60)
Late
ral Load (
kip
s)
Late
ral Load (
kN
)
Train Speed, km/h (mph)
Lateral Loads Acting on a Tangent Track
Lateral
Loads
- No correlation
between lateral loads
and train speed on
tangent track.
Leading axles of a 10-car freight
train (30, 33, and 36t axle loads).
Left Right
Tangent
Slide 21 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Lateral Loads Acting on a Curve Track
HIGH LOW
Lateral
Loads
5° curve
Leading axles of a 10-car freight
train (30, 33, and 36t axle loads).
0
2
4
6
8
10
12
14
16
18
0
10
20
30
40
50
60
70
80
3 (2) 24 (15) 48 (30) 66 (45)
Late
ral Load (
kip
s)
Late
ral Load (
kN
)
Train Speed, km/h (mph)
- Median load is ~5.5
times larger than
what was recorded in
tangent track.
Slide 22 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Variability in Loading Conditions
0 1 2 3 4 5 6
0
10
20
30
40
50
60
70
80
0
50
100
150
200
250
300
350
400
0 5 10 15 20 25 30
Lateral Load (kips)
Ver
tica
l Lo
ad (
kip
s)
Ver
tica
l Lo
ad (
kN)
Lateral Load (kN)
97 km/h, 60mph
24 km/h, 15mph
- Negligible correlation between lateral
and vertical loads on tangent track.
Slide 23 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
0 20 40 60 80 100
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0 50 100 150
Speed (mph)
Ve
rtic
al T
ie D
eflection (
in)
Ve
rtic
al S
leeper
De
flection (
cm
)
Speed (km/h)
Freight
Passenger
Negligible correlation between
train speed and sleeper deflection
Effect of Train Speed on Sleeper
Displacement
Slide 24 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
0 10 20 30 40 50 60
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0 50 100 150 200 250 300
Vertical Load (kips)
Ver
tica
l Tie
Def
lect
ion
(in
)
Ver
tica
l Sle
eper
Def
lect
ion
(cm
)
Vertical Load (kN)
24 km/h (15mph)
48 km/h (30mph)
97 km/h (60mph)
100% (Static Deflection)
90%
80%
60%
70%
50%
Deflections from train passes do
not exceed static response: about
60% (passenger) and 75% (freight)
Effect of Train Speed on Sleeper
Deflection (cont.)
Slide 25 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
0 10 20 30 40
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0 50 100 150
Rail Seat Load (kips)
Ver
tica
l Dis
pla
cem
ent
(in
)
Ver
tica
l Dis
pla
cem
ent
(cm
)
Rail Seat Load (kN)
Variability in Support Conditions
• Curve/Static Loads
• Each point = +22kN (+5kips) vertical load
• Low rail: weak support (slack or gap in support system)
• Low rail seat forces
• High rail: stiff boundary conditions (well-supported)
• High rail seat forces
HIGH LOW
Slide 26 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
0 10 20 30 40
0
5
10
15
20
25
30
35
40
0
20
40
60
80
100
120
140
160
180
200
0 50 100 150
Vertical Load (kips)
Rai
l Sea
t Lo
ad (
kip
s)
Rai
l Sea
t Lo
ad (
kN)
Vertical Load (kN)
Variability in Support Conditions
Nearly 95% of load is
transferred to rail seat
With a weak substructure much of the vertical load
(over 75%) is transferred to adjacent sleepers and resisted
by the bending of the rail
HIGH LOW
Slide 27 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Preliminary Findings with
Potential Design Considerations • The lateral loading demands were 5.5 times higher in the curve
than on tangent track
– Design should consider specialized components in the curve
• The vertical and lateral loading demands on tangent track are not
dependent on train speed
– Design should not weight speed highly on tangent track
• There is negligible correlation between concurrently acting lateral
and vertical loads on tangent track
• Dynamic vertical sleeper displacement never exceeded the purely
static response
• Rail seat forces are highly dependent on the stiffness of the
substructure and support conditions and can range from
below 20% to over 90% of the wheel-rail load
– Design should incorporate probabilistic loading conditions
Slide 28 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Future Work • Continued data analysis to understand the governing mechanics
of the system by investigating the:
– elastic fastener (clamp) strain response
– number of ties effected simultaneously
– bending modes of the sleepers
– pressure magnitude and distribution at the rail seat
• Continued comparison and validation of the UIUC finite
element model (Chen, Shin)
• Preparation for instrumentation trip (Summer 2013)
– Focus on lateral load path by gathering
• relative lateral sleeper displacements
• global lateral sleeper displacements
• load transferred to the clamp, insulator-post, and shoulder
• Small-scale, evaluative tests on Class I Railroads
Slide 29 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Acknowledgements
• Funding for this research has been provided by the
Federal Railroad Administration (FRA)
• Industry Partnership and support has been provided by
– Union Pacific Railroad
– BNSF Railway
– National Railway Passenger Corporation (Amtrak)
– Amsted RPS / Amsted Rail, Inc.
– GIC Ingeniería y Construcción
– Hanson Professional Services, Inc.
– CXT Concrete Ties, Inc., LB Foster Company
• Vince Peterson, Pelle Duong, George Righter
• Monticello Railway Museum (Tim Crouch)
• Transportation Technology Center, Inc.
– Dave Davis, Ken Laine, Dingqing Li, Steve Luna
• For assistance in instrumentation preparation:
– Harold Harrison, Michael Tomas, Jacob Henschen, Thomas Frankie
FRA Tie and Fastener BAA
Industry Partners:
Slide 30 Testing of Concrete Sleepers and Fastener Systems for the Understanding of Mechanistic Behavior
Questions?
Marcus Dersch
Department of Civil and Environmental Engineering
University of Illinois, Urbana-Champaign
Email: [email protected]