【摘要】 提出了多频分量相位演化零点时间的概念。对于复杂非平稳地震动过程,为降低求解多频分量相位演化零点时间的工作量,引入地震波波群演化的思想,在地震波相位谱敏感性分析的基础上,考察了典型实测地震动时程的模拟。结果表明,拟合地震动过程与实测非平稳地震动吻合较好,本文提出的相位谱重构方法具有重要的实践意义。同时,这一方法也为非平稳随机地震动建模提供了新的可能途径。更多还原

【Abstract】 A new concept of starting-time of phase evolution with multiple components of frequency is proposed in the present paper,which allows a feasible phase spectrum in the practical application just using few variables.It bypasses the need of the classical techniques in modeling the phase spectrum whereby tens even hundreds of variables are required.In order to reduce the computational effort of the starting-time for a complicated non-stationary ground motion process,a wave-group evolution formulation is also introduced of which the frequency points with significant contribution to ground motions are included.We further investigate the modeling of typical observed ground motions at certain type of soils where the key phase points are derived from the sensitivity analysis of phases of ground motions.For illustrative purposes,two observed ground motions at the type-Ⅱ site,i.e.Northridge and Chi-Chi ground notions,are investigated as examples.The numerical results reveal that the simulated ground motions match well to the original ground notions,indicating a significantly practical sense,which is inherent in the proposed simulation technique of phase spectrum.This simulation technique also provides a new scheme for the representation of non-stationary stochastic ground motions.更多还原