小舜江输水泵站厂房结构动力响应分析及安全评价

Dynamic Response Analysis and Safety Evaluation of Powerhouse Structure for Xiaoshunjiang Pumping Station

根据小舜江输水泵站工程结构特点,选取#3、#4机组段厂房结构及其地基建立了厂房结构的三维有限元模型,采用三维有限元动力时程分析方法分析了小舜江输水泵站厂房结构关键部位的应力和变形,并对其工作性态进行了安全评价。结果表明,关机工况下厂房结构的动拉、压应力极值均出现于#3机组段下游主梁跨中部位,最大动拉、压应力分别为0.829、-0.837MPa,均小于材料的抗拉和抗压强度设计值;开、关机工况下厂房结构在垂直方向上的振幅极值同样出现于#3机组段下游主梁跨中部位,开、关机工况下的最大振幅分别为0.352、0.815mm,均超出规范允许值0.15mm,因此需对泵站厂房结构振幅过大部位进行减振处理。

According to structural features of Xiaoshunjiang pumping station, powerhouse structure and foundation of unit # 3 and unit # 4 is selected to build a three-dimensional finite element model. Dynamic time-history analysis method of three-dimensional finite element is used to analyze the stress and deformation of key parts in powerhouse structure. And then the working state safety of powerhouse structure is evaluated. The results show that under shutdown conditions, the extrema of dynamic tensile stresses and pressure stresses of the powerhouse structure occurred in the mid-span parts of the downstream girder in unit # 3 segments; the maximum dynamic tensile stress was 0. 829 MPa while the maximum dynamic pressure stress was --0. 837 MPa these stress values were less than the design values the amplitude extrema of powerhouse structure in the vertical direction under startup and shutdown conditions occurred in the mid-span parts of the downstream girder in unit # 3 segments the maximum amplitude was 0. 352 mm while the maximum amplitude was 0. 815 mm under shutdown conditions these amplitude values were outside the allowable value, which was 0.15 mm. Therefore, some parts of powerhouse structure whose amplitude values were outside the allowable value are required to reduce the vibration.