基于材料损伤的水电站厂房上部结构地震易损性分析

Seismic vulnerability analysis of hydropower house superstructure based on material damage

水电站厂房上部钢筋混凝土框架-剪力墙结构在地震中易遭受破坏,基于材料损伤提出了上部结构抗震性能的评估方法,并采用有限元方法和增量动力分析法对厂房上部结构的地震易损性进行了分析。结果表明:水电站厂房上部结构主要的震损为墙柱的开裂以及混凝土保护层的剥落,核心区混凝土的压损伤较小,厂房上部结构具有较高的抗震安全储备,发生严重破坏甚至倒塌的概率很小;通过材料损伤可以方便地判断构件的开裂、压碎等状态,进而判断构件破坏程度;在结构无损伤或者损伤很小时,采用层间位移角或者基于材料损伤判断得到的结构易损性差别较小,在损伤程度较大时,层间位移角易出现偏差;采用材料损伤来判断结构的损伤状态是可行的,与层间位移角相比更为直接,适用性更广。

Reinforced concrete(RC)frame-shear wall structureas superstructure of a hydropower house is easy to be damaged under earthquake.Here,a method to evaluate aseismic performance of hydropower house superstructure based on material damage was proposed.The seismic vulnerability of powerhouse superstructure was analyzed using finite element analysis and incremental dynamic analysis.Results showed that the main seismic damage of hydropower house superstructure is cracking of its wall column and spalling of concrete protective layer,compressive damage of concrete in core area is smaller,the powerhouse superstructure has a high aseismic safety reserve and the probability of its serious damage or even collapse is very small;it is easy to judge states of cracking and crushing of components with material damage,and then judge damage degree of components;when the structure is not damaged or damaged very little,the difference of structural vulnerabilities obtained by using interlayer displacement angle or based on material damage judgment is smaller,and when the damage degree is larger,the interlayer displacement angle is easy to deviate;using material damage to judge damage state of the structure is feasible,compared to interlayer displacement angle,it is more direct and more applicable.