Investigation of a Highway Slope Failure on Yazoo Clay Using Electrical Resistivity Imaging (ERI)

Abstract

Yazoo clay is highly expansive in nature, which experiences shrink-swell behavior with seasonal moisture variations. Currently, concerning Yazoo clay characteristics, several natural and artificial slopes in Mississippi are vulnerable to failure due to a high volume of precipitation. Among available nondestructive methods to investigate the subsurface conditions, the Electrical Resistivity Imaging (ERI) method is becoming popular in recent years. Using the 2D ERI technique, the moisture variation at different soil layer depths can be easily detected. The current study investigates the failure of artificial highway slopes on Yazoo clay in Jackson, Mississippi. Qualitative evaluation of temporal moisture variation of the slope was conducted using ERI. The 2D ERI tests were conducted at the crest and toe of the 3H:1V slope. Based on the ERI test results, the overall degree of saturation was between 80% and 90%. The high-saturation condition indicated the formation of perched water zones.