Predicting the Performance of Highway Embankment Slopes

¹ Department of Civil and Environmental Engineering, Louisiana State University, Baton Rouge, LA 70803
² Department of Civil Engineering, The University of Texas at Arlington, Arlington, TX 76019
³ Department of Civil Engineering, South Dakota School of Mines & Technology, Rapid City, SD 57701

^* Corresponding author: njafari@lsu.edu

Abstract

Resilience of transportation infrastructure, such as highway embankments, is critical to avoiding commuter delays and costly repairs. The majority of highway embankments in Louisiana and Texas are in marginal condition because the high-plasticity clays that are used during construction will moisten with time to significantly lower strengths. The ring shear tests demonstrate that the Gamez and Stark [1] empirical correlations are applicable to Texas and Louisiana soils. The soil water retention curves at each site were fitted to the Van Genuchten model [2]. For example, the air entry values vary from 0.013 to 0.053 kPa-1 in Louisiana and from 0.008 to 0.01 kPa-1 in Texas. The implications of this wide range of air entry values is that the matric suction pressure required to saturate and desaturate controls the pore-water pressure build-up during a rainfall event.