裂隙干扰下降雨触发土质滑坡水土特征响应与稳定性演化OA

Revealing the influence mechanism of tensile cracks on slope seepage deformation and instability,this study investigates the role of crack depth in the spatiotemporal evolution of moisture infiltration and deformation within slopes under rainfall conditions.The research was conducted using physical model tests,which involved monitoring the dynamic changes in volumetric water content,pore water pressure,and wetting front throughout the slope failure process.The results indicate that crack depth directly determines the failure mode and movement extent of the slope by altering seepage efficiency and unloading space conditions.The ratio of crack depth to slope height is a key factor controlling the failure mode.When this ratio exceeds approximately one-third,the failure mode transitions from local progressive failure to sudden integral transitional failure.A larger ratio leads to more significant rainwater seepage and unloading effects,resulting in more integrated failure patterns and increased suddenness.The soil and water response of the slope shows a lag phenomenon,but the severity of the response is significantly increased,and the failure speed of the deep fracture slope is faster than that of the shallow fracture slope,and the peak displacement velocity is significantly increased.Tests on slope models with varying crack depths consistently show leading changes in hydraulic parameters,indicating that hydraulic softening is a precursor to slope failure.The evolution process generally follows a three-stage pattern:rapid response in the crack zone → local sliding →overall failure.This evolution closely corresponds to the displacement change pattern,which progresses through a stationary phase → slow creep → accelerated failure.The findings not only elucidate the time-sequential failure mechanisms of rainfall-induced slopes but also hold significant importance for the development of disaster prevention and mitigation strategies.