摘要
结合金安桥水电站B20堆积体边坡工程实例,基于动力时程分析原理,采用非线性动力有限元法,研究复合堆积体边坡地震动力响应特征,揭示边坡动位移、动应力、加速度响应规律,并计算边坡动抗滑稳定安全系数。计算成果表明:地震作用下,边坡将发生较大永久变形,量值达30cm;在堆积体及断层等部位主应力有显著集中效应,拉应力区较大;边坡中上部加速度有明显放大现象,尤其在堆积体,强地震时容易受激发而失稳;边坡动力安全系数存在低于1.0的情况,地震过程中部分区域存在失稳的可能,应加强支护措施。
Based on the principle of dynamical response time-dependent analysis,nonlinear finite element method was used to study the seismic characteristics of B20 slope with compound accumulation body in Jinanqiao Hydropower Station,and to reveal the response laws of dynamic displacement,stress and acceleration,with the calculating of the dynamic anti-slide safety coefficient during seismic time history. Study results show that：A greater permanent displacement would occur in the potential slide mass of the slope under earthquake,with maximum value 30 cm. A remarkable stress concentration would occur in such location as compound accumulation body and faults,with larger tensile stress zones. Acceleration in the middle and upside of slope compound was remarkably enlarged,especially in accumulation body,which was easy to fail during strong ground motion. Due to the dynamic safety coefficient possibly less than 1.0,the slope might lose its stability in some zone during strong ground motion.
基金
高等学校博士学科点专项科研基金资助项目(20090181120088)
四川省科技支撑计划项目(2008SZ0163)
关键词
岩土工程
强地震动
动力响应
稳定性
非线性有限元法
geotechnical engineering
strong ground motion
dynamic response
stability
nonlinear FEM
