基于系统动力学的卸加载响应比参数及其在堆积层滑坡稳定性评价中的应用

针对堆积层滑坡的物质组成和力学性质,从系统动力学角度,提出以卸加载响应比作为滑坡稳定性评价参数,并对卸加载响应比参数与加卸载响应比参数进行了比较和分析,指出卸加载响应比参数在边坡的稳定性评价和工程实践中更具有理论意义和实际应用价值。通过论证分析,确定了构成卸加载响应比的卸加载参数和卸加载响应参数,并论证了其合理性与可行性,在此基础上建立了月降雨量-位移加速度卸加载响应比模型。并以新滩典型堆积层滑坡为例,运用该模型进行分析计算,发现卸加载响应比时序曲线所反映的稳定状态与滑坡的实际状况基本吻合,当Y' Y'-且Y'0时,滑坡整体失稳,说明卸加载响应比参数和评价模型用于预测滑坡的变形阶段和作为失稳判据是行之有效的。

SYSTEM DYNAMICS BASED UNLOAD-LOAD RESPONSE RATIO PARAMETER AND ITS APPLICATION TO EVALUATING DEBRIS LANDSLIDE STABILITY

Aiming at the material composition and mechanical properties of the debris landslide, the theory that unload-load response ratio is taken as the evaluation parameter of landslide stability is put forward in the framework of system dynamics. Comparing and analyzing parameters of the unload-load response ratio and the load-unload response ratio, it is found that the unload-load response ratio parameters have more theoretical significance and practical application value in slope stability evaluation and engineering practice than the load-unload response ratio parameter. The unload-load response ratio parameter is determined and its feasibility is analyzed. Then, the model of unload-load response ratio, based on displacement acceleration and monthly rainfall, is established. As an example, the Xintan typical debris landslide is analyzed and calculated. The results show that the steady state reflected by the timing curve of the unload-load response ratio is consistent with the actual status. When Y' Y'- and Y'0,the overall unstability of landslide would appear. That shows it is available to use the unload-load response ratio to forecast landslide's deformation stage and as a criterion of landslide instability.