基于弹塑性损伤模型的预应力闸墩非线性有限元分析

常规的弹塑性模型由于没有考虑到损伤对结构强度的影响,常常得到高于结构实际承载力的应力分布,难以模拟破坏时由于内部损伤的累积导致的变形增加和承载力降低.将规范应力应变曲线进行简化,推导出弹塑性损伤模型曲线,采用简支纯弯梁验证了该简化模型的正确性,然后将该模型应用于深溪沟水电站预应力闸墩非线性有限元分析.计算结果表明考虑结构弹塑性损伤较线弹性分析能更好反应结构真实受力特性,计算结果对预应力钢筋的布置和闸墩的设计具有指导意义.

Nonlinear finite element analysis of prestressed pier based on elastoplastic damage model

Elastoplastic models can not explain accumulation of deformation and bearing capacity decrease caused by neglecting the damage evolution in ductile material;thus the stress distribution used to higher than the structure actual bearing capacity.Simplified elastoplastic damage model stress-strain curves are derived from specifications.Pure bending simply supported beam is used to prove the simplified curves correctness;then the curves are applied to nonlinear finite element analysis of the prestressed pier of Shenxigou hydropower station.The results are compared with linear elastic calculation results.The results show that the elastoplastic damage model better reflects the real stress distribution characteristics than linear elastic analysis.The results are significant to guidance the layout of prestressed reinforcement and prestressed pier design.