【摘要】 基于可靠度理论的概率极限状态设计法是结构设计的基本法则之一,而新一代"基于性能的地震工程"要求在性能化设计中尚应考虑随机因素的影响。为获得满足预设性能水准和可靠度指标的最优方案,以钢筋混凝土框架结构为例,根据其在不同性能水准下的位移需求,采用非线性随机有限元方法求解结构的抗震可靠度,并将可靠度指标作为约束条件,以总造价为优化目标,提出了一种基于性能和可靠度的抗震优化设计方法。其中,可靠度计算以OpenSees为平台,并采用基于梯度分析的FORM有限元法。优化分析以MATLAB为平台,通过程序调用,实现了与可靠度分析之间的数据通讯。算例分析表明,模拟退火算法在本问题中较遗传算法具有更高全局搜索能力和计算精度。研究成果可为新一代基于性能和可靠度的优化设计提供参考。更多还原

【Abstract】 The reliability-based limit state design method is one of the main principles in structural design,whereas the new generation performance-based earthquake engineering requires that the random factors should also be taken into account in the performance-based design.In order to obtain the optimal design that satisfies the target performance level and reliability indices,a performance-based and reliability-based seismic design optimization method is proposed.Taking the reinforced concrete frame as an example,the seismic reliability is calculated according to the displacement demands regarding various performance levels,using the nonlinear stochastic finite element method.The target reliabilitiy and the minimum material costs are used as constraints and the objective of the optimization problem,respectively.The first order reliability method(FORM) in conjunction with the nonlinear finite element analysis is adopted for the calculation of reliability indexes,which is made by using the OpenSees program.The design optimization is performed in the MATLAB environment,and uses the OpenSees to realize the data communication.A case study is made and it is observed that the Simulated Annealing algorithm has a higher global search ability and higher accuracy than the Genetic Algorithm in this case.This study provides references to the new generation performance-based and reliability-based seismic design optimization.更多还原