Model experimental study of asymptotic failure of slopes under rainfall conditions

Abstract

Loess landslides occur frequently due to climate change, anthropogenic disturbances and intensified engineering activities, and rainfall infiltration is one of the main causes. There is a need to study the deformation evolution mechanism of rainfall-induced loess landslides and to explore the influence of applied protective measures on slope stability. The loess slope at K615 km of Huangyan Expressway in Shaanxi Province, Yangpoyao slope, was selected as the research object, and the deformation, water content, pore water pressure, and soil pressure of the slope during rainfall were comprehensively monitored by designing two sets of physical model tests and combining with distributed optical fibre sensing and measurement technology. The result show that during rainfall infiltration, the increase in water content of loess slopes leads to a decrease in soil strength and an increase in pore water pressure, which ultimately triggers the evolutionary mechanism of slope destabilisation and damage. The second group of tests significantly slowed down the slope destruction process by burying plank protection measures, indicating that the protection measures have a positive effect on enhancing the stability of slopes. The research result provide an important basis for the disaster warning and prevention of rainfall-induced loess landslides, and also provide new ideas and method for the application of fibre-optic sensing technology in slope monitoring.

Keywords

model test / loess slope / distributed fibre optics / failure mechanism