Impact of tensile strength and incident angles on a soil slope under earthquake SV-waves

Abstract

The tensile strength and incident angles play important roles in seismically induced slope failures. In this paper, a new criterion for tension–shear coupling is proposed based on several sets of relevant lab data and is verified using the experimental data provided by previous researchers. This criterion can perfectly depict the tension region as well as the compression region in the entire stress space. Moreover, the tension–shear criterion was converted into an expression that could be directly used in a numerical method, and it was verified by a numerical example. In addition, the SV-waves were input using the equivalent nodal force method based on a viscous-spring artificial boundary. This process was implemented by the ABAQUS software, and two numerical examples were used to verify this method. Subsequently, based on the proposed new criterion and input method, the impacts of the strength criterion and incident angles on an analysis of seismically induced slope failures were studied. The results indicated that the evaluation of the tension–shear region is extremely important in the analysis of the seismically induced slope failures. The tensile strength of the seismically induced landslides was overestimated by the calculation of Mohr-Coulomb criterion owing to the ambiguous description of the tensile failure or the tension-shear failure, the assessment of the slope stability was thus not conservative. The incident angles of seismic waves affected the travel path and the directivity of slope seismic responses; the sliding displacement of the slope side near the epicenter rose with increasing angles of wave incidence, the critical slip surface deepened, and the hazard aggravated. Therefore, it is important to introduce both the tensile strength and incident angles when evaluating the stability of slopes subjected to seismic loads.