Dynamic tensile failure of a V-shaped canyon induced by vertically travelling SV waves

Abstract

Seismic-induced slope instability is a threat to transportation infrastructures in V-shaped canyons. The seismic-induced tensile cracks are commonly observed in the upper part of slopes and promote the seismic-induced slope instability. It is necessary to reveal the mechanism of tensile cracking in the upper part of a slope during an earthquake. The boundary integral equation method is employed to calculate the stresses induced by the self-weight and the vertically travelling SV wave. The stress development process shows that the self-weight induced stress plays an essential role in the development of tensile stress. Besides, the diffracted Rayleigh wave travelling along the ground surface is the major contributor to the generation of tensile stresses on the ground surface near the canyon. The effects of parameters, such as excitation frequency, canyon depth and slope inclination, on stress development are discussed. Parametric analyses indicate that the ground surface near a steeper slope more likely suffers tensile cracking. Higher-frequency waves prioritize producing the tensile cracks on the ground surface near a canyon. The steep slope of a deeper canyon allows the seismic waves within a wider frequency range to induce the tensile cracks on the ground surface near a canyon in priority.