Relative Operational Performance of Geosynthetics Used as Subgrade Stabilization

Print
General Information
Study Number: TPF-5(251)
Former Study Number:
Lead Organization: Montana Department of Transportation
Contract Start Date: Dec 01, 2011
Solicitation Number: 1266
Partners: ID, MT, NY, OH, OK, OR, SD, TX, WY
Status: Closed
Est. Completion Date: May 30, 2014
Contract/Other Number: 7712
Last Updated: Sep 08, 2014
Contract End Date: May 30, 2014
Financial Summary
Contract Amount:
Suggested Contribution:
Total Commitments Received: $633,719.00
100% SP&R Approval: Approved
Contact Information
Lead Study Contact(s): Susan Sillick
ssillick@mt.gov
Phone: 406-444-7693
FHWA Technical Liaison(s): Eric Weaver
Eric.Weaver@dot.gov
Phone: 202- 493-3153
Study Champion(s): Craig Abernathy
cabernathy@mt.gov
Phone: 406-444-6269
Organization Year Commitments Technical Contact Name Funding Contact Name
Idaho Department of Transportation 2012 $45,000.00 Tri Buu Amanda Laib
Idaho Department of Transportation 2013 $45,000.00 Tri Buu Amanda Laib
Montana Department of Transportation 2011 $150,719.00 Jeff Jackson Susan Sillick
New York State Department of Transportation 2012 $50,000.00 Bob Burnett Wes Yang
New York State Department of Transportation 2013 $50,000.00 Bob Burnett Wes Yang
Ohio Department of Transportation 2011 $50,000.00 Gene Geiger Jill Martindale
Ohio Department of Transportation 2012 $50,000.00 Gene Geiger Jill Martindale
Oklahoma Transportation 2012 $15,000.00 Jeff Dean Beckie Lyons
Oregon Department of Transportation 2011 $2,500.00 Justin Moderie Michael Bufalino
Oregon Department of Transportation 2012 $2,500.00 Justin Moderie Michael Bufalino
South Dakota Department of Transportation 2011 $25,000.00 Robert Longbons David Huft
Texas Department of Transportation 2011 $56,000.00 Mark McDaniel Ned Mattila
Texas Department of Transportation 2012 $32,000.00 Mark McDaniel Ned Mattila
Wyoming Department of Transportation 2011 $60,000.00 Jim Coffin Michael Patritch

Study Description

The Western Transportation Institute (WTI) recently completed a subgrade stabilization study for the MDT in 2009 (Cuelho and Perkins, 2009). This project was co-sponsored by NAUE GmbH & Co. KG (Germany), and used three of its products along with seven other geosynthetics to construct subgrade stabilization field test sections at the TRANSCEND research facility in Lewistown, MT. The test sections were constructed using a weak subgrade with a California Bearing Ratio (CBR) of 1.7 and with a relatively thin aggregate layer of 200 mm (8 in.). The aggregate layer was designed to carry fewer than 1000 traffic passes for sections without geosynthetics and more than 1000 traffic passes for sections with geosynthetics. The design was performed according to procedures contained in FHWA (1995) and checked against a more recent design method (Giroud and Han, 2004). The test sections reached a terminal rut depth of 100 mm (4 in.) in less than 40 truck passes. The mode of failure of most test sections was a clear bearing capacity (shear) failure in the subgrade and involved tensile rupture of several geogrid products and pullout of one geotextile product. The results showed that several products that would not meet the previous MDT specification performed better than several other products that did meet that specification for this specific case. It was also shown that the ultimate tensile strength and tensile strength at 2 percent axial strain were relatively important material properties in determining how well the geosynthetics performed under conditions of rapid rut development. These properties were most important because of the large loads the geosynthetic was required to support, which approached, and in some cases exceeded, the tensile strength of the materials. Subgrade stabilization for roadway construction generally requires that the subgrade geosynthetic-base layer system reaches a stable condition. This condition is typically assessed by observing the deformation of the system under the single pass of a loaded vehicle and observing that this deformation is minimal. Under stable conditions, bearing capacity failure of the subgrade has not occurred. In this operational condition, it is anticipated that other geosynthetic properties that might be more significant for conditions of smaller loads and deformations will be important for determining how well the material performs. The intention of the proposed research is to create these operational conditions in field test sections to determine which material properties are most responsible for showing good performance in subgrade stabilization applications.

Objectives

The main objective of this project is to determine material properties of geosynthetics that affect in-field performance of geosynthetics used for subgrade stabilization, so that DOT personnel can objectively and confidently select appropriate geosynthetics based on material properties and cost for a specific situation, while also allowing competition from different manufacturers.

Scope of Work

To accomplish the stated objective, test sections will be constructed at a controlled test site to investigate the relative benefit to an unpaved road of various geosynthetics available on the market. An artificial subgrade will be constructed to provide equivalent conditions for each test section; likewise the gravel surfacing along the entire test bed will be uniform to be able to make direct comparisons between geosynthetic products. Laboratory tests on the subgrade, base course and geosynthetics, as well as large-scale box tests conducted by a commercial testing laboratory, will be used to determine key material properties. Laboratory tests that will be used to characterize the materials used during this research project. Controlled traffic loading with frequent rut measurements will indicate performance benefits of each geosynthetic. Five basic measurements are necessary in this research project to quantify and understand the behaviors of the geosynthetic in the field test sections during trafficking: 1) longitudinal rut depth of the gravel surface, 2) transverse rut profile of the gravel surface, 3) displacement of the geosynthetic in the transverse direction, 4) strain in the geosynthetic in the transverse direction, and 5) pore water pressure in the upper layer of the subgrade. Additionally, post-traffic examination will provide invaluable information regarding the performance and installation survivability of the geosynthetics. Post-trafficking, forensic investigations will be conducted to evaluate damage to the geosynthetic from trafficking, as well as to re-evaluate pertinent soil strength characteristics. Intensive evaluations will take place in areas within each test section that have similar rutting. The base course will be removed from a sample area to carefully expose the geosynthetic. The geosynthetic will then be carefully removed from the area to analyze damage to junctions, rib integrity and material continuity. Samples of the extracted material will be removed to conduct monotonic tensile tests to evaluate changes in tensile strength during construction and trafficking, as well as to determine how much permanent strain was imparted in the material from construction and trafficking. Several DCP, LWD and in-field CBR measurements will be taken on the exposed subgrade surface within each test section. Additionally, the depth of the base course aggregate layer will be measured during these evaluations. The transverse rut profile of the base and subgrade will be measured on each side of the excavated area during these investigations to determine strain in the base course aggregate and characterize movement of the subgrade due to trafficking. Finally, the subgrade will be excavated from this area to comprehensively evaluate soil mixing between the subgrade and base course in the rutted areas, soil shear strength at various depths using the hand-held vane shear, and to facilitate a visual evaluation of the rutted area. Further analysis will be conducted to illustrate cost savings by optimizing material properties that most influence the design and performance of these materials, thereby increasing the knowledge base, confidence and efficiency for state DOTs to update their specifications.

Comments

The MDT would like to hear from those states who are interested in the project but may not be able to commit at this time.

Documents Attached
Title File/Link Document Category Document Type Privacy Document Date Download
GUSS Final Report http://www.mdt.mt.gov/other/webdata/external/research/docs/research_proj/subgrade/final_report-2.pdf Deliverable Final Report Public 2016-11-23
GUSS Project Summary Report GUSS_PSR.pdf TPF Study Documentation Study Summary Public 2014-09-01
Closeout Leter TPF-5(251) -- Close out Memo - Signed.pdf Memorandum Other Public 2014-09-08
Close-Out Spreadsheet CLOSE-OUT_SPREADSHEET.xlsx Other Other Public 2014-08-28
GUSS Progress Report No. 9 TPF QUARTERLY REPORT 9_SUBGRADE STABILIZATION_Q42013.PDF Progress Report Quarterly Progress Report Public 2014-01-31
GUSS Progress Report No. 8 GUSS-TPF-11-2013-QP.PDF Progress Report Quarterly Progress Report Public 2013-11-18
GUSS Task Report 3 TASK REPORT 3_SUBGRADE STABILIZATION-08-21-2013.PDF TPF Study Documentation Research Report Public 2013-08-15
GUSS Progress Report No. 7 GUSS-TPF-07-2013-QP.PDF Progress Report Quarterly Progress Report Public 2013-07-12
GUSS Progress Report No. 6 GUSS-TPF-04-2013-QP.PDF Progress Report Quarterly Progress Report Public 2013-04-11
GUSS Task Report 2 TASK REPORT 2_SUBGRADE STABILIZATION.PDF TPF Study Documentation Research Report Public 2013-02-15
Project Update Memorandum December 2012 PROJECT UPDATE MEMO_12-2012.PDF Memorandum Other Public 2012-12-15
GUSS Progress Report No. 5 GUSS-TPF-01-2013-QP.PDF Progress Report Quarterly Progress Report Public 2013-01-25
GUSS Progress Report No. 4 GUSS-TPF-10-2012.PDF Progress Report Quarterly Progress Report Public 2012-10-17
GUSS Progress Report No. 3 GUSS-TPF-07-2012-QP.PDF Progress Report Quarterly Progress Report Public 2012-07-15
GUSS Task Report 1 TASK REPORT 1_SUBGRADE STABILIZATION-04-15-2012.PDF TPF Study Documentation Research Report Public 2012-04-15
GUSS Progress Report No. 2 GUSS-TPF-04-2012-QP.PDF Progress Report Quarterly Progress Report Public 2012-04-10
GUSS Progress Report No. 1 GUSS-TPF-12-2011-QP.PDF Progress Report Quarterly Progress Report Public 2011-01-10
GUSS TPF 5(251) Proposal GUSS-PROPOSAL-WAGE-INFO-REMOVED-WEB-11-30-2011.PDF TPF Study Documentation Work Plan/Scope/Charter Public 2012-04-09
Acceptance Memo Document (2).pdf Memorandum Other Public 2011-06-28
Documents Attached
Title File/Link Document Category Document Type Privacy Document Date Download
Relative Operational Performance of Geosynthetics Used as Subgrade Stabilization http://www.mdt.mt.gov/research/projects/geotech/subgrade.shtml TPF Study Documentation Solicitation Public 2011-09-25

Relative Operational Performance of Geosynthetics Used as Subgrade Stabilization

General Information
Study Number: TPF-5(251)
Lead Organization: Montana Department of Transportation
Contract Start Date: Dec 01, 2011
Solicitation Number: 1266
Partners: ID, MT, NY, OH, OK, OR, SD, TX, WY
Status: Closed
Est. Completion Date: May 30, 2014
Contract/Other Number: 7712
Last Updated: Sep 08, 2014
Contract End Date: May 30, 2014
Financial Summary
Contract Amount:
Total Commitments Received: $633,719.00
100% SP&R Approval:
Contact Information
Lead Study Contact(s): Susan Sillick
ssillick@mt.gov
Phone: 406-444-7693
FHWA Technical Liaison(s): Eric Weaver
Eric.Weaver@dot.gov
Phone: 202- 493-3153
Commitments by Organizations
Organization Year Commitments Technical Contact Name Funding Contact Name Contact Number Email Address
Idaho Department of Transportation 2012 $45,000.00 Tri Buu Amanda Laib 208-334-8181 amanda.laib@itd.idaho.gov
Idaho Department of Transportation 2013 $45,000.00 Tri Buu Amanda Laib 208-334-8181 amanda.laib@itd.idaho.gov
Montana Department of Transportation 2011 $150,719.00 Jeff Jackson Susan Sillick 406-444-7693 ssillick@mt.gov
New York State Department of Transportation 2012 $50,000.00 Bob Burnett Wes Yang 518-457-4660 wes.yang@dot.ny.gov
New York State Department of Transportation 2013 $50,000.00 Bob Burnett Wes Yang 518-457-4660 wes.yang@dot.ny.gov
Ohio Department of Transportation 2011 $50,000.00 Gene Geiger Jill Martindale 6146448173 jacquelin.martindale@dot.ohio.gov
Ohio Department of Transportation 2012 $50,000.00 Gene Geiger Jill Martindale 6146448173 jacquelin.martindale@dot.ohio.gov
Oklahoma Transportation 2012 $15,000.00 Jeff Dean Beckie Lyons blyons@odot.org
Oregon Department of Transportation 2011 $2,500.00 Justin Moderie Michael Bufalino 503-986-2845 Michael.Bufalino@odot.oregon.gov
Oregon Department of Transportation 2012 $2,500.00 Justin Moderie Michael Bufalino 503-986-2845 Michael.Bufalino@odot.oregon.gov
South Dakota Department of Transportation 2011 $25,000.00 Robert Longbons David Huft 605-773-3358 dave.huft@state.sd.us
Texas Department of Transportation 2011 $56,000.00 Mark McDaniel Ned Mattila 512-416-4727 ned.mattila@txdot.gov
Texas Department of Transportation 2012 $32,000.00 Mark McDaniel Ned Mattila 512-416-4727 ned.mattila@txdot.gov
Wyoming Department of Transportation 2011 $60,000.00 Jim Coffin Michael Patritch 307-777-4182 michael.patritch@dot.state.wy.us

Study Description

Study Description

The Western Transportation Institute (WTI) recently completed a subgrade stabilization study for the MDT in 2009 (Cuelho and Perkins, 2009). This project was co-sponsored by NAUE GmbH & Co. KG (Germany), and used three of its products along with seven other geosynthetics to construct subgrade stabilization field test sections at the TRANSCEND research facility in Lewistown, MT. The test sections were constructed using a weak subgrade with a California Bearing Ratio (CBR) of 1.7 and with a relatively thin aggregate layer of 200 mm (8 in.). The aggregate layer was designed to carry fewer than 1000 traffic passes for sections without geosynthetics and more than 1000 traffic passes for sections with geosynthetics. The design was performed according to procedures contained in FHWA (1995) and checked against a more recent design method (Giroud and Han, 2004). The test sections reached a terminal rut depth of 100 mm (4 in.) in less than 40 truck passes. The mode of failure of most test sections was a clear bearing capacity (shear) failure in the subgrade and involved tensile rupture of several geogrid products and pullout of one geotextile product. The results showed that several products that would not meet the previous MDT specification performed better than several other products that did meet that specification for this specific case. It was also shown that the ultimate tensile strength and tensile strength at 2 percent axial strain were relatively important material properties in determining how well the geosynthetics performed under conditions of rapid rut development. These properties were most important because of the large loads the geosynthetic was required to support, which approached, and in some cases exceeded, the tensile strength of the materials. Subgrade stabilization for roadway construction generally requires that the subgrade geosynthetic-base layer system reaches a stable condition. This condition is typically assessed by observing the deformation of the system under the single pass of a loaded vehicle and observing that this deformation is minimal. Under stable conditions, bearing capacity failure of the subgrade has not occurred. In this operational condition, it is anticipated that other geosynthetic properties that might be more significant for conditions of smaller loads and deformations will be important for determining how well the material performs. The intention of the proposed research is to create these operational conditions in field test sections to determine which material properties are most responsible for showing good performance in subgrade stabilization applications.

Objectives

The main objective of this project is to determine material properties of geosynthetics that affect in-field performance of geosynthetics used for subgrade stabilization, so that DOT personnel can objectively and confidently select appropriate geosynthetics based on material properties and cost for a specific situation, while also allowing competition from different manufacturers.

Scope of Work

To accomplish the stated objective, test sections will be constructed at a controlled test site to investigate the relative benefit to an unpaved road of various geosynthetics available on the market. An artificial subgrade will be constructed to provide equivalent conditions for each test section; likewise the gravel surfacing along the entire test bed will be uniform to be able to make direct comparisons between geosynthetic products. Laboratory tests on the subgrade, base course and geosynthetics, as well as large-scale box tests conducted by a commercial testing laboratory, will be used to determine key material properties. Laboratory tests that will be used to characterize the materials used during this research project. Controlled traffic loading with frequent rut measurements will indicate performance benefits of each geosynthetic. Five basic measurements are necessary in this research project to quantify and understand the behaviors of the geosynthetic in the field test sections during trafficking: 1) longitudinal rut depth of the gravel surface, 2) transverse rut profile of the gravel surface, 3) displacement of the geosynthetic in the transverse direction, 4) strain in the geosynthetic in the transverse direction, and 5) pore water pressure in the upper layer of the subgrade. Additionally, post-traffic examination will provide invaluable information regarding the performance and installation survivability of the geosynthetics. Post-trafficking, forensic investigations will be conducted to evaluate damage to the geosynthetic from trafficking, as well as to re-evaluate pertinent soil strength characteristics. Intensive evaluations will take place in areas within each test section that have similar rutting. The base course will be removed from a sample area to carefully expose the geosynthetic. The geosynthetic will then be carefully removed from the area to analyze damage to junctions, rib integrity and material continuity. Samples of the extracted material will be removed to conduct monotonic tensile tests to evaluate changes in tensile strength during construction and trafficking, as well as to determine how much permanent strain was imparted in the material from construction and trafficking. Several DCP, LWD and in-field CBR measurements will be taken on the exposed subgrade surface within each test section. Additionally, the depth of the base course aggregate layer will be measured during these evaluations. The transverse rut profile of the base and subgrade will be measured on each side of the excavated area during these investigations to determine strain in the base course aggregate and characterize movement of the subgrade due to trafficking. Finally, the subgrade will be excavated from this area to comprehensively evaluate soil mixing between the subgrade and base course in the rutted areas, soil shear strength at various depths using the hand-held vane shear, and to facilitate a visual evaluation of the rutted area. Further analysis will be conducted to illustrate cost savings by optimizing material properties that most influence the design and performance of these materials, thereby increasing the knowledge base, confidence and efficiency for state DOTs to update their specifications.

Comments

The MDT would like to hear from those states who are interested in the project but may not be able to commit at this time.

Title File/Link Type Private
GUSS Final Report Deliverable Public
Closeout Leter TPF-5(251) -- Close out Memo - Signed.pdf Memorandum Public
GUSS Project Summary Report GUSS_PSR.pdf TPF Study Documentation Public
Close-Out Spreadsheet CLOSE-OUT_SPREADSHEET.xlsx Other Public
GUSS Progress Report No. 9 TPF QUARTERLY REPORT 9_SUBGRADE STABILIZATION_Q42013.PDF Progress Report Public
GUSS Progress Report No. 8 GUSS-TPF-11-2013-QP.PDF Progress Report Public
GUSS Task Report 3 TASK REPORT 3_SUBGRADE STABILIZATION-08-21-2013.PDF TPF Study Documentation Public
GUSS Progress Report No. 7 GUSS-TPF-07-2013-QP.PDF Progress Report Public
GUSS Progress Report No. 6 GUSS-TPF-04-2013-QP.PDF Progress Report Public
GUSS Task Report 2 TASK REPORT 2_SUBGRADE STABILIZATION.PDF TPF Study Documentation Public
GUSS Progress Report No. 5 GUSS-TPF-01-2013-QP.PDF Progress Report Public
Project Update Memorandum December 2012 PROJECT UPDATE MEMO_12-2012.PDF Memorandum Public
GUSS Progress Report No. 4 GUSS-TPF-10-2012.PDF Progress Report Public
GUSS Progress Report No. 3 GUSS-TPF-07-2012-QP.PDF Progress Report Public
GUSS Task Report 1 TASK REPORT 1_SUBGRADE STABILIZATION-04-15-2012.PDF TPF Study Documentation Public
GUSS Progress Report No. 2 GUSS-TPF-04-2012-QP.PDF Progress Report Public
GUSS TPF 5(251) Proposal GUSS-PROPOSAL-WAGE-INFO-REMOVED-WEB-11-30-2011.PDF TPF Study Documentation Public
Acceptance Memo Document (2).pdf Memorandum Public
GUSS Progress Report No. 1 GUSS-TPF-12-2011-QP.PDF Progress Report Public
Title File/Link Type Private
Relative Operational Performance of Geosynthetics Used as Subgrade Stabilization TPF Study Documentation Public

Currently, Transportation Pooled Fund is not supported on mobile devices, please access this Web portal using a desktop or laptop computer.