钢筋混凝土框架结构地震失效模式优化

地震作用下钢筋混凝土框架结构薄弱部位易发生损伤破坏,从而引起结构失效,针对结构的失效模式进行优化有利于提高结构的抗震性能.为此,以结构构件、结构层以及结构整体的损伤准则为约束方程,采用以结构构件损伤值相等为目标的优化设计方法,通过二次开发的钢材和混凝土的弹塑性损伤本构模型,应用纤维单元模型对强震作用下钢筋混凝土框架结构的失效模式进行了优化.以12层钢筋混凝土框架结构Benchmark模型为例,对双向El-Centro地震动作用下结构各构件的抗震性能进行优化,并对优化前后结构的动力响应和损伤发展进行分析,结果表明最优结构损伤集中得到有效的控制,结构各层损伤分布更加均匀,结构整体损伤减小,结构的抗震性能得到明显提高.

Failure Mode Optimization of Reinforced Concrete Frames Under Earthquake Excitations

The weak areas of reinforced concrete frames are prone to damage,which may cause structural failure under earthquake,and optimizing the structural failure mode is favorable for the improvement of the seismic performance of the structures. In this paper, the damage criteria of the structural elements,the stories of the structure and the overall structure taken as constraint equations, the failure mode of the reinforced concrete frame structure under strong earthquake is optimized by means of a secondary development of elastoplastic damage constitutive models for steel and concrete. The target of the optimized method is to make the damage value of the structural elements equal. As a numerical example,the 12-storey Benchmark reinforced concrete frame structure is optimized under bi-directional El-Centro earthquake. At the same time,the dynamic response and damage development of the structure are analyzed before and after the optimization. The analysis results show that the story damage distribution of the optimal structure is more uniform than that of the initial structure,the damage value of the structure is reduced,and the proposed optimization method can effectively avoid the weakness of the structure and significantly increase the global seismic performance of the building.