【摘要】 基于非平稳随机地震动模型,编制快速合成人工地震动的程序以实现对工程地震动的随机抽样。对工程岩体地震响应进行等效线性数值计算时,定义结构面的水平等效加速度(时程),将结构面水平等效加速度(时程)的最大值超过其屈服加速度(滑移阈值)作为岩体失稳的极限条件;基于地震动随机抽样和等效线性化时程计算,提出一种随机地震动作用下工程岩体沿结构面的滑移概率和稳定可靠度的计算方法。考察某工程岩体在附近3个潜在震源影响下的结构面的滑移概率和稳定可靠性。结果表明,震级相差不大时,远场地震诱发该工程岩体的失效概率小于0.01%;近场地震作用下,工程岩体的失效概率为26.1%。更多还原

【Abstract】 Based on non-stationary random vibration model,a series of ground motions were synthesized,whose statistical parameters could satisfy the randomness of a potential earthquake.In order to evaluate the stability of engineering rock mass,horizontal equivalent acceleration( HEA) of the rock mass joint plane was defined,while the earthquake response of engineering rock mass was calculated numerically.The maximum horizontal equivalent acceleration( MHEA) was compared with the yield acceleration of the rock mass joint plane.Based on non-linear numerical calculations and ground motion samples of an earthquake,a new approach was proposed to calculate the probability density of the MHEA of rock mass joint plane.The application of this method in seismic reliability analysis of engineering rock mass was demonstrated.The numerical computation results indicate that the probability of rock mass instability under remote earthquake is below 0.01%,while the value is up to 26.1% under near earthquake,given the same magnitude of earthquake.更多还原