HORIZONTAL STRAIN - SLOPE STABILITY CORRELATION CONSIDERING THE EFFECT OF SHALLOW EXCAVATION NEAR THE SLOPE TOE

Abstract

The stability of a soil slope, as initially estimated by design calculations, may be adversely impacted by construction activities near the slope toe, such as excavating foundation pits. This study aims to evaluate the impact of shallow foundation pit location on existing slope stability. The regression function correlating the factor of safety with average horizontal strain is established to analyze this influence. Numerical simulations of homogeneous slopes using Plaxis 2D software, employing the strength reduction method (SRM), are conducted to determine the horizontal deformation field and factor of safety. From 22 numerical test data, a regression function of the factor of safety and average horizontal strain has been built. The results indicated that only at a distance of less than 2m from the toe of the slope to the excavation edge, the presence of excavation reduces the overall stability of the existing slope. Additionally, for slopes with different heights but similar slope angles and physico-mechanical characteristics, excavations at the same distance from the toe, there is a correlation between the average horizontal strain and the factor of safety. Therefore, establishing the regression function is the basis for giving the level of landslide warning for the existing slopes when one has the measurement of the horizontal strain of the slope.