【摘要】 在考虑地震动空间变化效应的基础上,提出了模拟完全非平稳多点人工波的思路,并用MATLAB编写了相应的程序。针对Clough-Penzien功率谱密度函数,建议了模拟多点地震动的峰值因子的取值。该方法不仅全面考虑了地震动的空间变化效应,即行波效应、部分相干效应和局部场地效应,而且在考虑地震动强度非平稳特性的同时,还考虑了频率非平稳特性。强度非平稳特性通过传统的包络函数来考虑,频率非平稳特性通过相位差谱来体现。用周期-频度谱验证了人工波的频率非平稳特性,并用不规则指数分析了地震波的不规则程度。分析表明:生成的人工波具有明显的强度和频率非平稳特性,而且能较好的反映硬土场地和中硬土场地上地震动随距离的衰减特性。更多还原

【Abstract】 Simulation method of completely non-stationary artificial wave is proposed on the basis of considering its spatial variability,and realized by programming with MATLAB procedure.Aiming at the power spectral density function of Clough-Penzien model,value of peak ratio of ground motion in simulation is suggested.Not only the overall spatial variability of wave passage effect,loss of coherency and the role of local site condition are considered,but also the non-stationary of both amplitude and frequency is taken into consideration. Non-stationarity of amplitude is expressed by the traditional envelope function,and frequency non-stationarity is incarnated by phase difference spectrum.The frequency non-stationarity of artificial wave is verified by spectra of periodfrequency,and level of irregularity is analyzed by irregularity index.The results indicate that: the non-stationarity of phase and frequency is obviously reflected in the generated artificial waves,and so is the attenuation of wave amplitude in firm site and middle firm site.更多还原