论文部分内容阅读
采用基于小波变换的多向地震动速度脉冲特性鉴定方法,从NGA数据库及汶川地震动记录中提取出了196条速度脉冲地震动数据;基于Newmark非耦合滑动模型,考虑土体非线性特征。通过计算速度脉冲地震动作用下不同强度(ky)及初始自振周期(Ts)边坡模型的地震位移,对比分析了边坡地震位移与速度脉冲地震动参数之间的相关性,并建立了适用于近断层速度脉冲地震动的边坡地震位移统一预测模型。结果表明:既有边坡地震位移预测模型低估了近断层速度脉冲地震动引起的位移值,而用于预测近断层非脉冲地震动引起的边坡地震位移离散较小;近断层速度脉冲地震动引起的边坡地震位移与其速度脉冲特性密切相关,地震位移与速度脉冲地震动参数(峰值速度PGV)相关性最好;采用1.5倍边坡自振周期对应的加速度反应谱(Sa(1.5Ts))和PGV分别代表速度脉冲地震动的频谱成分及速度脉冲特征,能够综合反映速度脉冲地震动对边坡地震位移的影响;建立了基于边坡参数(ky,Ts)和脉冲地震动参数(PGV,Sa(1.5Ts))的边坡地震位移预测模型,为考虑近断层地震动速度脉冲特性影响的边坡地震位移概率灾害分析提供了基础。
A total of 196 velocity impulsive ground motion data were extracted from the NGA database and Wenchuan ground motion records using the method of multi-directional ground motion pulse characteristics identification based on wavelet transform. Based on the Newmark non-coupled slip model, the nonlinear characteristics of soil were considered. By calculating the seismic displacement of the slope model with different intensity (ky) and initial natural period (Ts) under the action of velocity pulse earthquake, the correlation between slope seismic displacement and velocity pulse ground motion parameters is analyzed and compared A Unified Prediction Model for Slope Earthquake Displacement Suitable for Pulsed Ground Motion Near-Fault Velocity. The results show that the displacement prediction model of the existing slope underestimates the displacement caused by the near-fault-velocity pulse ground motion, while the slope displacement used to predict near-fault non-pulsation ground motion is small. The near-fault-velocity pulse ground motion The seismic displacement is related to the velocity pulse characteristics. The correlation between the seismic displacement and the velocity pulse ground motion parameter (peak velocity PGV) is the best. The acceleration response spectrum (Sa (1.5Ts) ) And PGV represent the spectral components and velocity pulse characteristics of velocity pulse ground motion, respectively, which can comprehensively reflect the influence of velocity pulse ground motion on slope seismic displacement. Based on the slope parameters (ky, Ts) and pulse ground motion parameters (PGV , Sa (1.5Ts)), which provides the foundation for the hazard analysis of slope earthquake displacement probabilistic impact on the pulse characteristics of near-fault ground motions.