考虑流固耦合与上部结构影响的半地下厂房地震响应模拟

Seismic Response Simulation of Semi-underground Powerhouse with Considering Fluid-solid Coupling and Superstructure

某中型电站半地下厂房,采用后浇带设计方案,即在板、墙、梁相应位置留设临时施工缝,若干时间后再浇注该施工缝混凝土,浇筑完成之后厂房成为一个整体结构,不存在变形缝,此类大跨度水电站厂房比较少见.在考虑了流固耦合与上部结构的影响下,针对该厂房在三向耦合地震激励下的各典型运行工况的振动特性及应力应变情况进行了分析.结果表明,流固耦合对反映厂房在有水工况下的自振特性具有较大的影响,流固区的范围差值导致厂房的不协调振动是影响该厂房地震响应幅值的主要原因;并且当地震发生时,1、2号机或3、4号机同时发电运行对于厂房结构的应力状态最为不利,为此类半地下厂房的抗震设计和安全运行提供可靠参考.

Amedium-sized semi-underground powerhouse,later pouring design plan,with temporary construction joint located at corresponding area of board,wall,beam,then pouring concrete into construction joints,so,the powerhouse become an overall structure,such powerhouse of large-span is relatively rare.Considering the influence of fluid-solid coupling and superstructure,an analysis of vibration characteristics,stresses and strains of the powerhouse under three different directions earthquake,is carried out.The results show that the fluid-solid coupling has a great effect on the natural vibration characteristics of powerhouse under water conditions.The difference of fluid-structure zones leads the incompatible vibration.It is the main reason for the extreme affect of seismic response.When the earthquake occurs,the condition of No.1,2 or 3,4 machines running is the most unfavorable stress of powerhouse.The conclusion gives a reliable reference for design and operation of such semi-underground power house.