一种改进的近断层脉冲型地震动模拟方法

An Improved Approach for Near-fault Pulse-like Ground Motion Simulation

本文基于小波包技术的随机地震动模拟方法,提出一种改进的参数化随机近断层脉冲型地震动模拟方法。然后,通过识别和提取近断层脉冲型地震动数据库中脉冲型地震动的特征参数,建立了基于震源、传播路径和场地特征等参数的脉冲模型参数预测方程。最后,通过模拟实际记录和误差分析检验了改进的模拟方法的有效性。结果表明:应用改进的模拟方法得到的地震动时程无论在波形、频率特性还是峰值上均与实际记录具有较好的一致性。改进的模拟方法在保留地震动时频非平稳性的基础上,能够有效地提高近断层脉冲型地震动的模拟效果,并且能够很好地体现脉冲型地震动的主要特征。

In this paper, an improved parameterized stochastic simulation method of near-fault pulse-like ground motion is proposed based on the stochastic ground motion simulation method using the wavelet packet method. Then, by identifying and extracting the characteristic parameters of pulse-like ground motions in a set near-fault ground motions database, the prediction equation of pulse model parameters in terms of the earthquake source, path and site characteristic parameters is established. Finally, the improved simulation method is verified by simulating recorded pulse-like ground motions and error analysis. Our results illustrate that simulated time histories of pulse-like ground motions by improved simulation method is well consistent with the recorded one in terms of waveform, frequency characteristic and peak value. The improved simulation method can effectively improve the simulation results of near-fault ground motion under retain time-frequency nonstationary of ground motion, and can also well reflect the main characteristics of pulse-like ground motion, which has very important engineering application value.