承载开闭钢屋盖的预应力混凝土看台结构抗震性能研究

Seismic performance of a prestressed concrete stadium structure supporting a retractable steel roof

为了深入探索承载开闭钢屋盖的预应力混凝土看台结构的抗震性能,针对上海旗忠森林体育城网球中心开闭钢屋盖与预应力混凝土看台组成的结构体系,继振动台模型试验后,采用弹塑性有限元分析,对比研究了主振型为扭转的结构体系的反应特点、屋盖闭合与开启状态对预应力结构抗震性能的影响、闭环式倒锥台空间框架结构体系的弹塑性地震反应规律和破坏模式。研究发现:屋盖的不同状态影响结构的振动特性和地震反应;以扭转为主振型的闭环式看台结构在水平地震作用下的响应模式为平动形式;预应力看台结构罕遇地震后的整体性能良好;闭环式倒锥台空间框架构形限制了大震下结构的侧移,相对于平行式框架,能提高对重力荷载的抗倒塌能力。本研究增进了对有开闭屋盖的结构体系及闭环式框架结构体系的抗震性能认识,有助于这类结构的设计。

In order to explore the seismic performance of a prestressed concrete stadium structure supporting a retractable steel roof, the structure of the Shanghai Qizhong Tennis Center, consisting of a retractable steel roof and a prestressed concrete stadium, is studied by using elasto-plastie finite element analysis and shaking table test. The following issues are investigated： the effects of the roof configurations in opening and closing and the pre-stress on the structural seismic response, the general behavior and failure mechanism of the stadium spatial frame systems featured with circularly arranged columns and inverse-cone stands. It is found that the roof status has great effect on the natural period, vibration mode and seismic response of the entire structure, the stand response to horizontal seismic excitation is stronger in roof opening configuration than in closing configuration and the response mode is dominantly translational rather than rotational, though the stand is characterized by its fundamentally torsional vibration mode. The study indicates that the prestressed inverse-cone stands keep the system from global side-sway collapse under gravity loads, even in case that most columns lost moment capacity.