某抽水蓄能电站地下厂房结构体系抗振研究

Study on Vibration Resistance of Underground Power House Structure System of A Pumped Storage Power Station

以某大型抽水蓄能电站为例,采用不同的地下厂房结构布置方案,即楼板采用板梁结构或厚板结构、上下游侧采用边墙结构或立柱结构、改变立柱结构的截面尺寸,提取结构的模态,分析了厂房结构的自振特性,并基于谐响应法分析了额定工况条件下不同方案之间动力特性的差异和楼板厚度敏感性。结果表明,在机组动荷载作用下,改变楼板结构形式或采用不同截面尺寸的立柱在一定范围内对厂房整体的自振特性作用有限;从厂房抗振角度来说,上下游侧采用边墙结构比立柱结构更有利;当厚板结构的厚度达到0.7m时,与现有板梁结构的抗振能力基本相当;就一般情况而言,板梁结构的抗振能力要高于厚板结构。因此,应结合工程实际情况来选择最优的结构体系布置方案。

Taking a large-scale pumped-storage power station as an engineering example,the underground power house adopts different structural arrangement schemes,such as adopting plate girder structure or slab structure for the floor slab,adopting the side wall structure or pillar structure on the upstream and downstream sides,and changing the sectional size of the pillar structure.And then the self-vibration characteristics of the power house structure ares analyzed by extracting its structural modes.Based on the harmonic response method,the difference of dynamic characteristics between different programs is analyzed under nominal conditions,and the floor thickness sensitivity is also analyzed.The results show that changing the floor structure or adopting pillars with different cross-sectional dimensions has limited effect on the natural vibration characteristics of the whole plant within a certain range under the action of dynamic load of the unit.From the standpoint of power house vibration resistance,the use of sidewall structures on the upstream and downstream sides is more advantageous than the column structure.The calculation found that when the thickness of the slab structure reaches 0.7 m,the vibration resistance of the existing slab beam structure is basically the same.As far as the general situation is concerned,the anti-vibration capability of the plate girder structure is higher than that of the thick plate structure.Therefore,we should choose the optimal structural system layout scheme according to the actual situation of the project.