冻融循环作用下边坡地震动稳定性研究

The Freeze-thaw Cycling Effects on Slope Stability in Earthquake

季节冻土区和多年冻土区边坡在经历冻融循环后其力学性质产生较大变化,边坡稳定性随之改变,在地震动荷载作用下存在着巨大的安全隐患。本文基于FLAC数值软件,将考虑冻土相变的显热熔算法引入热学计算模块,并结合静态边界动力计算模块,建立了适用于冻融循环条件下的边坡地震动稳定性分析平台。研究了冻融循环对边坡土体地震动稳定性的影响。结果表明,在发生冻融循环的季节冻土区或多年冻土已经退化的区域,地震动后边坡的塑性破坏形式主要取决于发生冻融循环的活动层的范围。

In seasonal and permanent permafrost region, the soil mechanical properties may be changed considerably in construction work, which is potentially threat to the stability of infrastructure during earthquakes. This paper develops an analysis platform for the slope earthquake stability considering freeze-thaw cycling based on FLAC. The platform embedded an explicit specific heat algorithm to reflect the ice-water phase change effect. The effects of freeze-thaw cycling on slope earthquake stability are analyzed. The results indicate that the range of active layer is a main factor influencing the plastic destroying form.