摘要
应用三维有限元强度折减法对两河口土石坝进行坝坡稳定性分析,将坝体典型断面特征点竖直向与顺河向两者的合成位移矢量与强度折减系数之比作为判断坝坡破坏的标准,当其比值出现突变或达到极限值时即认为坝坡处于极限平衡状态,此时的强度折减系数即为坝坡的安全系数。利用临界破坏状态时坝坡的位移矢量等值线图来研究潜在的滑动面的位置及形状。分析表明:强度折减法计算得到的坝坡稳定安全系数比条分法略小,利用坝体典型断面特征点处的竖直向与顺河向的合成位移矢量的变化趋势作为坝坡破坏标准,物理意义明确,结果可靠。同时,在一定范围内,施工荷载分级越多,坝坡稳定安全系数相应增大;蓄水分级越多,对坝坡的稳定越有利。
3-D FEM strength reduction method is used to analyze the slope stability of Lianghekou rockfill dam.We adopt the ratio of resultant displacement vectors of typical points to strength reduction factor as the dam slope failure criteria,and the resultant displacement vectors consist of stream-direction displacements and vertical ones.When the ratio appears a sudden change or reaches a limit value,the dam slope is in the limit balance state and the strength reduction coefficient is suggested to be safety factor of the slope.The position and shape of potential sliding surface are studied by displacement vector contour map in the critical failure state.It is showed that the safety factor calculated by strength reduction is slightly smaller than that calculated by slice method,and resultant displacement vector′s variation trend has clear physical meanings and reliable results as the failure criteria.Moreover,the research shows that in a certain range,the more grades of construction load,the larger of the stability safety factor;the more grades of impoundment,the more stable the dam slope is.
出处
《人民长江》
北大核心
2010年第3期67-70,共4页
Yangtze River
基金
江苏省自然科学基金项目(BK2007582)
关键词
强度折减法
有限元分析
坝坡稳定
条分法
土石坝
strength reduction method
FEM
slope stability
slices method
rockfill dam
