Estimating Subgrade Resilient Modulus for Pavement Design
http://ww2.mackblackwell.org/web/research/ALL_RESEARCH_PROJECTS/2000s/2007-dennis/2007Schwarz.html
Record Type: UTC, DOT

The Arkansas State Highway and Transportation Department (AHTD) designs its pavement structures in accordance with the 1986/1993 American Association of State Highway and Transportation Officials (AASHTO) Guide for the Design of Pavement Structures. These procedures include an evaluation of the support characteristics of a subgrade soil in terms of resilient modulus (MR) and it has been used almost exclusively in design practice over the past 20 years. The resilient modulus parameter is not measured by the AHTD, but rather, it is typically estimated from R-Value test results. This convention was accepted primarily to avoid equipment and labor expenses that would be associated with the resilient modulus test. Previous research sponsored by the AHTD suggests that current pavement designs are conservative and basically no fundamental relationship exists between the R-Value and the MR parameter for subgrade soils. This project aims to improve the resilient modulus prediction method by developing a material model for subgrade soil based on correlation of soil index properties with the resilient modulus parameter. Index properties for soils are measured by tests that are relatively simple, inexpensive, and repeatable, unlike either test to determine the resilient modulus or R-Value. Correlation of index properties to resilient modulus of a soil has the potential to provide a more accurate and cost effective means for estimating the MR parameter used for pavement design. Development and implementation of the proposed methodology and pavement design guidelines will emphasize mechanistically-based design criteria, generate savings in areas including soil testing and material/construction costs, and contribute to improving pavement performance and design life.
Start date: 1999/8/15
End date: 2005/1/31
Status: Active
Contract/Grant Number: MBTC-2007
Total Dollars: 166613
Source Organization: Arkansas State Highway and Transportation Department
Date Added: 04/22/2004
Index Terms: Arkansas, Construction, Costs, Pavement design, Pavements, Research projects, Resilience, Soils, Structures, Subgrade (Pavements), Subgrade materials, American Association of State Highway and Transportation Officials, Moisture content,

University of Arkansas, Fayetteville
http://www.mackblackwell.org/
Mack Blackwell National Rural Transportation Center
4190 Bell Engineering Center
Fayetteville, AR 72702
USA

McDaniels, Karen L.
Phone: (501) 569-2580
Fax: (501) 569-2070
Email: karen.mcdaniels@ahtd.state.ar.us

University of Arkansas, Fayetteville
http://www.mackblackwell.org/
Mack Blackwell National Rural Transportation Center
4190 Bell Engineering Center
Fayetteville, AR 72702
USA

Dennis, Norman D.
Phone: (501) 575-2933