Progressive failure mechanism of a large bedding slope with a strain-softening interface

Abstract

The present work is primarily concerned with the progressive failure mechanism of a large bedding slope with a strain-softening interface. Both the laboratory tests and finite difference method (FLAC software) are employed to fulfill our purpose. Firstly, the shear properties of the interface (the mudded weak interlayer) are investigated through groups of repeated shear tests. According to the test results, all kinds of the interfaces share the characteristics of strain softening. To simulate the shear behavior of the interface in FLAC, a contact constitutive model with strain softening is built and verified against experimental results. The modified constitutive model of the interface is later applied to the numerical simulation of the bedding slope. Through investigating the response of the strain-softening contact elements to the stress characteristics among the rock layers, the chain action law of the bedding slope stability can be obtained. Finally, the progressive failure mechanism of the bedding slope is determined based on the chain action law. A typical case is investigated to validate the feasibility of the strain-softening contact element and the progressive failure mechanism of bedding slopes.