【摘要】 针对降雨触发的滑坡,以斜坡平面滑动失稳为例,考虑滑面介质的应变软化和水致弱化性质,提出了一个简单的力学模型,并运用突变理论分析其失稳的力学机制。在突变分析中,通过尖点突变模型,详细讨论了刚度比、含水量,几何-力学参数等因素对滑坡孕育和触发过程的影响。结果表明:斜坡演化过程是其内部因素和外部因素共同作用的结果,其中内部因素起主导的定性作用,外部因素起触发作用。通过突变分析发现,一个完整的滑坡孕育演化过程包括5个阶段:稳定～减速滑动～匀速滑动～加速滑动～剧滑。从整体上深化了对斜坡失稳机理的认识。更多还原

【Abstract】 The landslide is considered as a consequence of catastrophic slide of initially stationary or creeping slope triggered by a small perturbation,such as the effect of rainfall. Presuming that slope is shallow and infinitely long and the slip surface is made up of elasto-brittle medium and strain-softening medium,a cusp model of two control parameters,a and b,is formulated with simple law of mechanics. A fully catastrophe analysis is done for all possible scenarios when a continuous change is imposed to the control parameters. As the slip surface is continuous and erosion due to rainfall occurs,the control parameters of the slip surface may evolve such that a previously stable slope may become unstable (e.g. catastrophe occurs),with a small perturbation imposed. Thus the present analysis offers a plausible explanation to why slope failure occurs at a particular rainfall,which is not the largest in the history of the slope. Through catastrophe analysis,it is also found that a complete evolution of landslide includes five stages:stable～slowing slide～uniform slide～accelerating slide～catastrophic slide.更多还原