【摘要】 库岸边坡的变形破坏及稳定性研究是目前国内外研究的热点之一。基于水电站库区一大型堆积体边坡,通过现场原位直剪试验获取岩土体的力学参数,利用岩土数值分析FLAC3D软件,考虑了堆积体与基岩基覆接触带介质的应变软化特性,对水库蓄水和下降过程中边坡的变形破坏特征进行了分析预测。结果表明,在库水升降作用下变形主要发生在堆积体内部;根据堆积体的变形特征可分为3个区:前缘牵引变形区,变形量最大;中间过渡区,变形量最小;后缘被牵引变形区,变形量介于前缘和中间之间。模拟过程中,在坡体的不同位置设置位移监测点,得到了蓄水和水位下降过程中各监测点的位移时程曲线,监测结果显示,水位下降时堆积体前缘易形成局部失稳。通过剪应变增量判断堆积体边坡在库水作用下可形成2个潜在的滑动破坏面。更多还原

【Abstract】 Research on deformation and stability of reservoir bank slopes is one of the focus in the world.Taking a deposit slope in the hydropower reservoir area for example,the deformation and failure characteristics of the slope are predicted by FLAC3D while the reservoir level is rising and rapid drawdown.It is indicated that deformation mainly occurred in the deposit body while the reservoir level fluctuating;the deposit body is divided into three regions according to the deformation characteristics: the front traction deformation area with the largest deformation,the middle transition area with the smallest deformation and the posterior passive traction deformation area.Displacement monitoring points are set at different places of the slope body;so the displacement-time graphs during reservoir filling and rapid drawdown of reservoir level are obtained.The monitoring results show that the local instability occurred at the front of the slope during the rapid drawdown of the reservoir level.Owing to the influence of water two potential sliding failure surfaces in slope can be judged based on the shear strain increment.更多还原