甘孜地区残坡积层状边坡的动力失稳机理研究

国道317线俄岗公路地处高中山剥蚀地貌区，区内构造作用强烈，地震频发，高海拔气候特点突出，残坡积边坡分布广泛。对此，通过现场调查分析确定出残坡积边坡具有倾斜分层的坡体结构特征，设计了振动台模型试验和数值模拟方案，研究了边坡的动力响应和失稳破坏模式。研究结果表明:频率较高时，输入地震动峰值越大，放大系数越小；若边坡体出现塑性屈服，则放大系数变化规律不明显；斜层状边坡的动力破坏面为层内圆弧面与层间界面的组合。

Study on Dynamic Instability Mechanism of Residual Soil Slope in Ganzi Region

E’gang Section of National Highway 317 is located in the high and middle mountainous denudation area, wherein earthquake occurs frequently as a result of strong tectonism; besides, the climatic features of high altitude are prominent, and residual soil slope spreads widely. Through field investigation, the structure characteristics of inclined multilayer of residual soil slope was defined herein; then with shaking table model test and numerical simulation solution designed hereto, the dynamic response and stability failure mode of the slope were studied. The result shows that, when the frequency is higher, the peak value of input ground motion is larger, and the magnification factor is smaller; once plastic yield of the slope body occurs, the change law of magnification factor is not obvious; the dynamic failure surface of inclined slope is a combination of in-layer arc surface and inter-layer interface.