ABSTRACT

Gauss–Newton algorithm is originally applied for estimating constant-ductility energy factor spectra of near- and far-fault ground motions. First, constant-ductility energy factors are clarified, a three-parameter exponential equation relating energy factor to period is proposed and estimation of parameters of the proposed equation by means of Gauss–Newton algorithm is fully demonstrated. A set of 100 both pulse-like and non-pulse like near-fault ground motion records and 112 ordinary far-fault ground motion records is assembled as seismic input. Mean energy factor spectra of the utilized ground motions are preliminarily computed from nonlinear time history analyses for five constant ductility ratios ranging from 2 to 6, and then the same spectra are estimated by Gauss–Newton method. Very strong correlation between the computed and the estimated energy constant-ductility energy factor spectra is observed after few iteration steps.

摘要

Gauss-Newton 算法最初用于估计近断层和远断层地面运动的恒定延性能量因子谱。首先，阐明了恒延性能量因子，提出了能量因子与周期的三参数指数方程，并充分论证了利用高斯-牛顿算法对所提出方程的参数估计。将一组 100 个脉冲类和非脉冲类近断层地震动记录和 112 条普通远断层地震动记录组合起来作为地震输入。利用非线性时程分析初步计算了利用地震动的平均能量因子谱，对从 2 到 6 的五个恒定延性比进行了初步计算，然后通过 Gauss-Newton 方法估计了相同的谱。