三峡电站15^#机组厂房结构动力分析

Dynamic response analysis on No.15 unit powerhouse structure in the Three Gorges Hydropower Station

由于蜗壳直接埋入法施工比较方便,三峡电站15#机组拟采用直接埋入法。本文在已有静力研究成果的基础之上,建立了15#机组厂房结构的有限元模型,分析了蜗壳外围混凝土开裂后厂房的整体自振特性,以及在设计地震作用下厂房结构的地震响应。研究结果表明,蜗壳周围混凝土开裂对15#机组厂房整体自振特性影响较小,这说明15#机组左边边墙增加了厂房结构的整体刚度。同时,在设计地震作用下,竖向最大动应力为1.38MPa,两者都出现在右边墙体,这说明左边边墙能增加15#机组厂房的抗震能力。

Compared with the bedding laying method and the pressure retaining laying method, the spiral casing direct laying method can make reinforced concrete to bear higher hydraulic pressure. Its construction method is simpler than the others two methods, therefore the direct laying method is intended to be adopted for the No. 15 unit of the Three Gorges Hydropower Station. Based on the static research work, a finite element model of the No. 15 unit powerhouse has been built, and an analysis to the selfoscillation characteristics of the integral powerhouse with local cracks and its earthquake response under design seismic shock, has been carried out. The result shows that the local concrete cracks have little effects on the integral self-oscillation characteristics of the powerhouse, and that the vertical stress of walls is 1. 38MPa under design earthquake condition. According to the distributing regularities of earthquake response, a conclusion can be made that the left sidewall would enhance the anti-earthquake performance of No. 15 unit powerhouse.