Railway Substructure

17
MidCon(nent Research Forum 2012 September 6 Keene, Edil, Tinjum, & Brown University of WisconsinMadison Slide 1 UW – Madison Geological and Geotechnical Engineering Geological Engineering Transporta1on Geotechnics Civil & Environmental Engineering University of Wisconsin-Madison Andrew Keene, Jim Tinjum, Tuncer Edil, and Randy Brown Railway Substructure Stabilization with Polyurethane Injections

description

Railway Substructure

Transcript of Railway Substructure

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  1  

UW – Madison  Geological and

Geotechnical Engineering    

Geological  Engineering  Transporta1on  Geotechnics  Civil  &  Environmental  Engineering  

University of Wisconsin-Madison

Andrew Keene, Jim Tinjum, Tuncer Edil, and Randy Brown

Railway Substructure Stabilization with Polyurethane Injections

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  2  

Outline   Background

•  Problem •  Motivation

  Materials •  Rigid-Polyurethane Foam (RPF) •  Polyurethane-Stabilized Ballast (PSB)

  Methods for Mechanical Property Evaluation •  Plastic deformational behavior •  Compressive and flexural properties

  Feasibility of Strategically Placed Polyurethane Layer in Track-Substructure •  Evaluate track mechanical behavior after stabilization

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  3  

Background: Railway Track Components

  Deterioration in the substructure leads to permanent deformation in the track, threatening rail operations

  Prevent track deformation while enhancing rail operations

  Ballast layer deteriorates under numerous loading repetitions Problem:

Objective:

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  4  

Motivation: Track Maintenance Costs   Maintenance of ballast is $500M/ year

•  For 150,000 km of Class 1 freight rail in the US, (Chrismer and Davis 2000)

Fouling Level Increases During Service Life of Track

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  5  

Types of Fouling

(Ebrahimi et al. 2010)

Coal Fouling Mineral Fouling Clay Fouling

Non-­‐Cohesive  Fouling  (i.e.,  between  P4  &  P200)   Cohesive  Fouling  (i.e.,  P200)  

P4 = 4.75 mm; P200 = 0.075 mm

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  6  

UW-Madison Railroad Research   Mitigating Ballast Fouling Impact and Enhancing Rail

Freight Capacity •  Prevent ballast layer deterioration and track deformation •  Enhance railway track capacity and maintained capabilities •  Polyurethane reinforcement of ballast layer is proposed

Steve Reed

Dr. Randy Brown Andrew Keene

Ben Warren

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  7  

Materials: Uretek USA Inc. Polyurethane

  Uretek Polyurethane: Rigid-Polyurethane Foam High density, expanding, thermoset, resin system

  Reaches 90% of full compressive and tensile strength in 15 minutes

  Research Involves Use of Technology With Rail Ballast

Rigid-Polyurethane Foam (RPF) Polyurethane-Stabilized Ballast (PSB)

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  8  

Methods: Large-Scale Cyclic Triaxial (LSCT)

300-mm

600-mm

Cyclic loading machine to simulate railway traffic

Automated data acquisition system (LabView)

Axle load: 20, 30, and 40 tons

Equivalent to: Deviator Stress, σ = 300 kPa Confining Stress, σ = 90 kPa

(Ebrahimi 2011)

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  9  

Flexural Beam Testing

L = 0.4 m

Unconfined Compressive Strength Testing

L = 0.76 m

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  10  

0

0.5

1

1.5

2

2.5

3

3.5

300 350 375 400

Cum

ulat

ive

Plas

tic S

trai

n, ε

P (%

)

Deviator Stress, σd (kPa)

Fouled Ballast, FI 5% & MC 15%

Clean Ballast

PS-Clean Ballast

PS-Fouled Ballast, FI 25% & MC 15%

PS-Recycled Ballast, P25.4 mm & R19 mm

Results: Stabilized and Un-stabilized

MC = % Moisture Content FI = Fouling Index (%)= P4+P200

Clean Ballast Reference Line

PS = Polyurethane Stabilized P4 = 4.75 mm P200 = 0.075 mm

Tested over 200,000 loading repetitions in cyclic triaxial compression

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  11  

PSB and Constituent Mechanical Properties

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

Com

pres

sive

Flex

ural

Tens

ile

Com

pres

sive

Flex

ural

Tens

ile

Com

pres

sive

Flex

ural

Tens

ile

PSB RPF Ballast

Mec

hani

cal S

tren

gths

(kPa

)

0

50

100

150

200

250

300

350

400

450

500

Com

pres

sive

Flex

ural

Tens

ile

Com

pres

sive

Flex

ural

Tens

ile

Com

pres

sive

Flex

ural

Tens

ile

PSB RPF Ballast

Elas

tic M

odul

i (M

Pa)

ρRPF = 200 kg/m3

ρb = 1,580 kg/m3

RPF = Rigid Polyurethane Foam

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  12  

Material Property Summary

  Mechanical Properties •  PSB plastic deformational behavior far less than clean

ballast, recycled ballast, and fouled ballast •  PSB elastic moduli typically less than ballast

  Further Considerations and Restated Questions: •  Effect of lower modulus on overall track response? •  Fatigue lifecycle for PSB layers?

  Next Step: Modeling PSB in Track-Substructure

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  13  

PSB Model – Percolation-Injection

RPF = Rigid Polyurethane Foam

  Concept: Model percolation-injection method for PSB stabilization

  Goal: Determine track elastic response

  Result: Areas of lower modulus did not have negative impact

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  14  

3D–View

Longitudinal View

Lateral View PSB Trackbed Layer

PSB Model – Subsurface-Injection

  Concept: Model subsurface-injection method for PSB trackbeds

  Goal: Determine strain at base of layer for input into analytical fatigue model

  Result: Strain measured would give PSB fatigue lifecycle at 500-1000 MGT

RPF = Rigid Polyurethane Foam εt = Flexural Strain

(Rose & Konduri 2006)

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  15  

Conclusions

  Mechanical Properties

•  PSB outperforms other track-substructure materials

•  PSB had typically higher elastic deformational behavior

  Feasibility of Stabilization in Track-Substructure

•  Stabilization does not have negative impact on elastic response

•  Injection methods are feasible for track stabilization

•  PSB can greatly increase track mechanistic lifecycle

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  16  

Future Work   Ballast Stabilization with Polyurethane:

•  Evaluation of polyurethane-stabilized ballast with varying levels of fouling and water content

•  Use of method in field-scale tests or track maintenance operations

  Warning System and Inspection Project: •  Correlate fouling conditions found using GPR and TDR with track

deformation measure with FOS

•  Select track segment for case study evaluation of inspection methods

  University of Wisconsin-Madison Rail Research: •  Incorporate results from Mechanistic and non-destructive evaluation

research into test track or field application

•  Continue to advance geotechnical approaches for enhancing track inspection techniques, maintenance prediction, and sustainability using mechanistic-based research

•  Evaluate impacts of frac sand loads on new and existing Wisconsin rail infrastructure

Mid-­‐Con(nent  Research  Forum  2012  September  6  Keene,  Edil,  Tinjum,  &  Brown  University  of  Wisconsin-­‐Madison      Slide  17  

Questions?

Acknowledgements

  Center for Freight Infrastructure Research and Education (CFIRE)

  Uretek USA Inc.

  UW-Madison Laboratory Staff: •  William Lang

•  Xiaodong ‘Buff’ Wang

  Special Thanks To: •  Dr. Ali Ebrahimi

•  Zhipeng Su

References

ASTM Standards, Annual Book of ASTM Standards, ASTM International, West Conshohocken, PA

Ebrahimi, A. (2011). “Deformational Behavior of Fouled Railway Ballast.” PhD thesis, Department of Civil and Environmental Engineering, University of Wisconsin, Madison.

Ebrahimi, A. and Keene, A.K. Maintenance Planning of Railway Ballast, In proceedings of the AREMA 2011 Annual Conference, Minneapolis, Minnesota, September 18-22.

Keene, A. (2012). “Mitigating ballast fouling and enhancing rail-freight capacity.” MS thesis, Dept. of Civil and Env. Eng., University of Wisconsin-–Madison.

Rose, J.G. & Konduri, K.G. (2006). "KENTRACK–A Railway Trackbed Structural Design Program." AREMA 2006 Annual Conference, Louisville, Kentucky, September 17-20. •  Gizem Bozkurt

•  Ben Warren