在OPEnSEES中实现了一种最近研究的新型防屈曲支撑结构(brbS)的弹塑性本构模型的隐式算法,并基于直接微分法(dIrECT dIffErEnTIATIOn METHOd,简称ddM),推导实现其响应的参数敏感性分析算法。此模型能够很好地预测brbS的实验结果。同时,根据敏感性计算结果能够分析brb本构参数对结构响应的影响和相对重要性,分析结果可用于基于梯度计算的结构优化、结构可靠性和模型修正中。选取一个配置brbS的4层钢框架进行实例研究,用ddM计算结果与有限差分法(fInITE dIffErEnCE METHOd,简称fdM)计算结果进行对比,以验证ddM敏感性分析算法的正确性、精度和效率,并分析了brb模型参数对全局和局部响应的影响。此外,响应敏感性分析结果还用于有限元模型修正中,以验证brb模型敏感性分析结果对于提高优化算法效率的作用。Buckling-restrained braces(BRBs)model and its sensitivity analysis algorithm based on direct differentiation method(DDM)are carried out using OpenSees.This model is able to predict the nonlinear behavior of BRB systems,and the DDM analysis results can provide the effect of constitutive parameters on structural response and show its relative importance.The research is useful for any gradient-based methods like structural optimization,structural reliability analysis,and model updating.A non-moment resisting 4-storey steel frame with BRBs subjected to accelerograms is studied to verify the correctness,accuracy and efficiency of the DDM algorithm.The influence of the constitutive parameters of each BRB on global and local response is also analyzed in this paper.In addition,response sensitivity results are used in updating a finite element model to verify the effect of the results on improving the algorithm efficiency.国家自然科学基金项目(51261120376); 中央高校基本科研业务费项目(2010111075)资
