PREDICTION OF RESILIENT MODULUS FROM SOIL INDEX PROPERTIES

Subgrade soil characterization in terms of Resilient Modulus (M sub R) has become crucial for pavement design. For a new design, M sub R values are generally obtained by conducting repeated load triaxial tests on reconstituted/undisturbed cylindrical specimens. Because the test is complex and time-consuming, in-situ tests would be desirable if reliable correlation equations could be established. Alternately, M sub R can be obtained from correlation equations involving stress state and soil physical properties. Several empirical equations have been suggested to estimate M sub R. The main focus of this study is to substantiate the predictability of the existing equations and evaluate the feasibility of using one or more of those equations in predicting the M sub R of Mississippi soils. This study also documents different soil index properties that influence M sub R. Correlation equations developed by the Long Term Pavement Performance (LTPP) program, Minnesota Road Research Project, Georgia DOT, Carmichael and Stuart Drumm et al., Wyoming DOT, and Mississippi DOT are studied/analyzed in detail. Eight road (subgrade) sections from different districts are selected and soils tested (TP 46 Protocol) for M sub R in the laboratory. Other routine laboratory tests are conducted to determine physical properties of the soil. Validity of the correlation equations are addressed by comparing measured M sub R to predicted M sub R. In addition, variations expected in the predicted M sub R due to inherent variability in soil properties is studied by the method of point estimates. The results suggest that LTPP equations are suited for purposes of predicting M sub R of Mississippi subgrade soils. For fine-grain soils, even better predictions are realized with the Mississippi equation. A sensitivity study of those equations suggests that the top five soil index properties influencing M sub R include moisture content, degree of saturation, material passing the #200 sieve, plasticity index and density.

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• Record URL:
  https://rosap.ntl.bts.gov/view/dot/16187
• Record URL:
  https://rosap.ntl.bts.gov/view/dot/24156
• Supplemental Notes:
  • Title on documentation page: Resilient Modulus Prediction Employing Soil Index Properties.
• Corporate Authors:

  University of Mississippi, University

  Department of Civil Engineering
  University, MS  United States  38677

  Mississippi Department of Transportation

  401 North West Street, P.O. Box 1850
  Jackson, MS  United States  39215-1850

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • George, K P
• Publication Date: 2004-11

Language

• English

Media Info

• Features: Appendices; Figures; References; Tables;
• Pagination: 72 p.

Subject/Index Terms

• TRT Terms: Density; Equations; Laboratory tests; Mathematical prediction; Measurement; Modulus of resilience; Moisture content; Pavement design; Percent saturation; Plasticity index; Sieve analysis; Soils; Subgrade (Pavements); Test sections; Validation
• Identifier Terms: Long-Term Pavement Performance Program
• Geographic Terms: Mississippi
• Subject Areas: Data and Information Technology; Design; Geotechnology; Highways; Pavements; I22: Design of Pavements, Railways and Guideways; I42: Soil Mechanics;

Filing Info

• Accession Number: 00987786
• Record Type: Publication
• Report/Paper Numbers: FHWA/MS-DOT-RD-04-172,, Final Report
• Contract Numbers: State Study 172
• Files: NTL, TRIS, USDOT, STATEDOT
• Created Date: Mar 30 2005 12:00AM