高大型井塔结构的抗震设计优化

Anti-seismic Optimum Design for Large Shaft Tower Structure

高大型井塔结构计算复杂,特殊荷载种类多,抗震薄弱环节突出。结合内蒙古某主井井塔结构抗震设计的实例,从平面与竖向布置、特殊荷载、结构计算等方面分析了高大型井塔结构抗震薄弱的主要原因,即井塔的底层刚度小、楼板开洞面积大、荷载分布不均匀、建筑高宽比大、顶部不能设置中柱等;通过三维有限元分析与设计软件PMSAP的分析计算,提出了高大型井塔结构抗震设计薄弱环节的解决方案,即加大底层刚度、加大楼板刚度、调整楼面梁布置、加大底部楼层重量、加大基础嵌固层深度等;基于PMSAP从刚重比、有效质量系数、剪重比、周期比、位移比等方面对井塔结构抗震设计进行验算与分析,以为实际井塔工程提供数据和经验,并指出井塔须进行水平振动验算,将水平强迫振动频率与抗震计算得出的结构自振频率对比,以避免提升设备与井塔本身产生共振。

The structure of the large shaft tower is complex because of various kinds of special loads and the obvious weakness of seismic design. Combined with the seismic design example of a main shaft tower in In- ner Mongolia, the paper analyzes the main reasons for the weak anti-seismic of large scale shaft tower structure from the aspects of plane and vertical arrangement, special load, calculation of structural rigidity. There are other causes, for instance, the bottom stiffness is small, the floor opening area is large, the load distribution is uneven,the height to width ratio of building is big, the top cannot be placed in the middle column etc. Based on the analysis of three-dimensional finite element software and the calculation of PM- SAP design software, the paper puts forward the design solution for the anti-seismic weak link, the solution is to increase the bottom stiffness, increase floor stiffness,adjust the floor beam layout,increase the floor weight,and increase the depth of the foundation embedment layer. The paper also analyzes the seismic