基于统计线性化的非线性随机振动虚拟激励法研究及应用

传统的虚拟激励法成功地解决了结构线性随机地震响应计算效率低的问题,却无法将非线性因素考虑在内。以统计线性化理论为基础,提出了一种可以考虑结构非线性的改进的绝对位移直接求解的虚拟激励法,采用不同的抗震分析方法,对一座单塔双索面预应力混凝土斜拉桥进行位移、速度、加速度功率谱密度以及位移、轴力响应值的计算,并进行对比分析,结果表明所提出改进的虚拟激励法不仅可以考虑结构的非线性,而且精确、高效,可以广泛地应用于桥梁工程的抗震分析中。

Pseudo excitation method for nonlinear random response calculation based on statistical linearization technique and its application

Traditional pseudo excitation method successfully solved the problem of low efficiency of calculation for linear structure's seismic random vibration, but it cannot take nonlinearity into account. Based on statistical linearization technique, it puts forward a kind of improved pseudo excitation method which can consider structure’s nonlinearity, and it directly solves the absolute displacement. A prestressed concrete cable-stayed bridge which has a single tower and double cable has been taken as an example. The power spectral density of displacement, velocity and acceleration, and the response value of displacement and axial force have been calculated using different seismic analysis methods. Through the comparative analysis, the results show that the improved pseudo excitation method can not only consider the structure's nonlinearity, but also has high accuracy and efficiency. It can be widely used in bridge's seismic analysis.