采用随机响应面法钢筋混凝土框架抗震全局灵敏度分析

采用基于多项式混沌展开的随机响应面方法,建立结构输出响应的代理模型,求得各输入变量的基于方差分析的全局灵敏度指标.之后以层数不同的三个钢筋混凝土框架结构为应用对象,使用Open Sees软件进行有限元建模,并采用该方法对结构进行整体承载能力极限状态下的抗震全局灵敏度分析,将求得的各输入变量的灵敏度指标绘于同一图中,比较不同输入变量对结构响应的影响大小.从求得的全局灵敏度指标可知,影响结构抗震可靠度的主要因素为地震作用的不确定性以及结构的钢筋屈服强度.该结果符合工程经验判断,进一步说明所采用的方法具有较高的可行性和计算精度.

Seismic global sensitivity analysis of RC frame structures through stochastic response surface methods

In this thesis the stochastic response surface methods based on polynomial chaos expansions are used to construct the surrogate model of the structural response. Then the global sensitivity indices of the input variables based on analysis of variance (ANOVA) are calculated by this model. Three reinforce concrete frame structures whose floor numbers are different are taken as case study, and are modelled by OpenSees. The global sensitivity indices for the load carrying capacity limit state of structures are calculated by this method and plotted in the same figure. Then the influence of each input variable to the structural response is compared. Through the study of this thesis, some conclusions can be summarized. The main factor which influences the anti-seismic properly of RC frame structures is the uncertainty of the seismic actions and the yield strength of the reinforcement. This conclusion is in agreement with the engineering empirical judgments, which proves that the method in this thesis has enough feasibility and calculating accuracy.