Designing and Constructing Permanent Stable Foundation Layers in Areas of Sulfate Rich Soils
The presence of a suitable foundation layer plays a significant role in the constructability and long-term performance of pavements. During construction, these layers must provide sufficient support for placement and compaction of subsequent pavement layers, and during service life, these foundation layers play a critical role in the pavement structure by supporting the upper pavement layers and spreading loads to provide long-term pavement performance. When designed correctly, lime stabilized layers have a long history of providing permanent support in areas of plastic soils. However, lime has been removed from recent projects because of concerns over soluble sulfates. The use of select fill and geogrids has not provided projects with the support needed to successfully complete construction, and in some cases even handle construction traffic. These failures cost millions of dollars to fix and result in significant project delays. Adequate and permanent foundation layers are critical to performance of both flexible and rigid pavement structures. The research team will document the effectiveness of current practices for identifying sulfates on construction projects and determine if new or improved technologies exist to more effectively and reliably detect sulfates. The research team will deploy these tools on actual construction projects and document their effectiveness. Using advanced lab testing, the research team will determine treatment alternatives for soils containing sulfates. Based on the findings, the research team will recommend soil treatment or pavement structural design alternatives to provide permanent and stable foundation layers. The findings from this project shall be used to recommend updates to project selection, treatment guidelines, test procedures, specifications, and the Pavement Manual.
Language
- English
Project
- Status: Active
- Funding: $582,301.25
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Contract Numbers:
0-7242
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Sponsor Organizations:
Texas Department of Transportation
125 E. 11th Street
Austin, TX United States 78701-2483 -
Managing Organizations:
Texas Department of Transportation
125 E. 11th Street
Austin, TX United States 78701-2483 -
Project Managers:
Smith, Anne
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Performing Organizations:
Texas A&M Transportation Institute
Texas A&M University System
3135 TAMU
College Station, TX United States 77843-3135 -
Principal Investigators:
Sebesta, Stephen
- Start Date: 20260501
- Expected Completion Date: 20260831
- Actual Completion Date: 0
Subject/Index Terms
- TRT Terms: Compaction; Pavement base course; Pavement design; Pavement layers; Soil stabilization; Soils; Sulfates
- Subject Areas: Construction; Design; Geotechnology; Highways; Materials; Pavements;
Filing Info
- Accession Number: 01995306
- Record Type: Research project
- Source Agency: Texas Department of Transportation
- Contract Numbers: 0-7242
- Files: RIP, STATEDOT
- Created Date: Jul 10 2026 4:37PM