大型水电站厂房结构地震时程响应非线性数值模拟

Seismic time history and non-linear numerical simulation of large-scale power-house structure

以往对水电站厂房结构进行动力分析时常被视为弹性体,在对其进行地震响应分析时,常采用反应谱分析方法,而实际的厂房结构是弹塑性的,不很大的拉应力即可产生裂缝。本文提出一种新的分析方法,即采用地震时程分析法并考虑材料的非线性因素,对某大型水电站厂房结构进行抗震研究。研究表明,这种方法能够反映厂房结构在地震荷载作用下其响应随时间变化的全过程,能够展现裂缝出现的位置、时间和破坏形态。这种方法的提出,对大体积混凝土结构进行基于性能的抗震研究及安全评估,具有重要的意义。

Powerhouse structure has been usually looked as an elastic body for dynamical analysis and the seismic reaction has been often analyzed by response spectrum method until the present, but the materials of power-house structure are elastoplastic in nature, small tensile stress may induce cracks. A new method is proposed to study a large-scale power station structure in this paer, which is a time history response analysis method with considering non-linear factors for structure analysis. The study result shows that the complete dynamic response process of structure varying with loads is showed with time history method, and the position time and damaging style are showed when the cracks appear. It is valuable for anti-seism study based on the capability and safety evaluation.