地震荷载作用下顺层岩质边坡安全系数分析

结合强度折减法的思想,并考虑到地震荷载特征以及离散元法和顺层岩质边坡的特点,提出一种求解地震荷载作用下顺层岩质边坡安全系数的方法。采用关键点位移/速度时程曲线的变化趋势对边坡的临界状态进行判断,采用失稳状态时坡体的速度/位移矢量图来判断与安全系数对应的滑动面。将上述方法运用到钟家湾顺层边坡的稳定分析中,并将所得结果与极限平衡法计算结果进行对比,发现二者的计算数值相差较小,对比结果表明该方法是合理可行的。在此基础上,利用UDEC初步分析地震荷载作用下坡高、坡度、岩层倾角以及地震波参数包括振幅、频率等因素对顺层岩质边坡安全系数的影响规律。

FACTOR OF SAFETY ANALYSIS OF BEDDING ROCK SLOPE UNDER SEISMIC LOAD

Based on the strength reduction method,a new method to determine the factor of safety of bedding rock slope under seismic load is proposed.The equilibrium condition is estimated based on the trend of the key points' displacements or velocities.The slide surface is also determined by the velocity or displacement vectors of the unstable condition.Based on the new method,the factor of safety of Zhongjiawan bedding slope is calculated by UDEC and compared with the results obtained by limit equilibrium method(LEM).It is revealed that the value calculated by UDEC is close to that by LEM,which indicates that the new method is feasible and reasonable.The influences of height and angle of bedding slope,inclination of interface as well as seismic parameters including amplitudes and frequency on the factor of safety of bedding rock slope under seismic load are analyzed.