论文部分内容阅读
对于孔深达到100m,但剪切波速低于500m/s的深厚土层,首先论述了计算其地震反应时输入基底的常用处理方法,然后基于理论分析和工程实例,建立了3个输入基底(线性外推、软弱夹层假定、坚硬基底)模型,结合土层非线性试验数据,使用一维等效线性化程序计算了不同强度地震作用下各模型的反应。对地表加速度峰值和反应谱进行了对比分析,指出坚硬基底模型建模简单,结果偏安全,适于工程应用。最后,通过多个基底波速值对地表反应影响的敏感性分析,提出了坚硬基底剪切波速的合理取值为相邻土层波速值的1.3~1.4倍,且不低于500m/s。
For the deep soil with the hole depth of 100m and the shear wave velocity of less than 500m / s, the common processing methods for calculating the seismic response into the substrate are discussed. Then, based on theoretical analysis and engineering examples, three input substrates Linear extrapolation, soft mezzanine assumption, hard base) model, combined with the soil nonlinear experimental data, the one-dimensional equivalent linearization program was used to calculate the response of each model under different seismic intensity. Comparing and analyzing the peak acceleration and response spectrum of the ground surface, it is pointed out that the rigid base model is simple and the result is safe and suitable for engineering application. Finally, based on the sensitivity analysis of the effects of multiple base-wave velocities on the surface reactions, the reasonable value of the shear wave velocity of hard basalts is 1.3-1.4 times of the wave velocity of the adjacent soils and not less than 500 m / s.