Analytical exploration of γ-function explicit method for pseudodynamic testing of nonlinear systems
It has been well studied that the γ-function explicit method can be effective in providing favorable numerical dissipation for linear elastic systems. However, its performance for nonlinear systems is unclear due to a lack of analytical evaluation techniques. Thus, a novel technique is proposed herein to evaluate its efficiency for application to nonlinear systems by introducing two parameters to describe the stiffness change. As a result, the numerical properties and error propagation characteristics of the γ-function explicit method for the pseudodynamic testing of a nonlinear system are analytically assessed. It is found that the upper stability limit decreases as the step degree of nonlinearity increases; and it increases as the current degree of nonlinearity increases. It is also shown that this integration method provides favorable numerical dissipation not only for linear elastic systems but also for nonlinear systems. Furthermore, error propagation analysis reveals that the numerical dissipation can effectively suppress the severe error propagation of high frequency modes while the low frequency responses are almost unaffected for both linear elastic and nonlinear systems.
作 者： Shuenn-Yih Chang Yu-Chi Sung 作者单位： Department of Civil Engineering, National Taipei University of Technology, Chinese Taipei 106-08 刊 名： 地震工程与工程振动（英文版） SCI 英文刊名： EARTHQUAKE ENGINEERING AND ENGINEERING VIBRATION 年，卷(期)： 2005 4(1) 分类号： P315 关键词： pseudodynamic test nonlinear error propagation numerical dissipation