地铁车站大跨预应力混凝土顶板静载试验研究

Experimental study on static load of underground station with large-span prestressed concrete roof

大跨无柱地下车站以其跨度大、空间开阔、内部设施布置灵活等优点已成为现在地铁建设的主流。依托某地铁大跨无柱车站工程,引入预应力技术,通过进行缩尺试验和有限元模拟,重点研究了采用顶梁预应力技术与弱连接节点形式的试验模型的裂缝开展情况、荷载-位移曲线和承载能力等指标。试验及有限元分析结果表明:将预应力技术引入顶梁的方式提升了结构的整体受力性能,预应力筋整体布置连贯,传力方式明确,可以很好地解决大跨地铁车站结构受力、裂缝控制、挠度控制等问题。

Large-span column-free underground station has become the mainstream of subway constructions because of its advantages such as large span,wide space and flexible arrangement of internal facilities.Based on the study of one underground station,this paper introduced prestressed technology into large-span column-free underground station.Through scale test and finite element simulation,the crack development,load-displacement curve and load-bearing capacity of the test model with the prestressed technology of the top beam and the weak connection joint were studied.The test results and finite element analysis showed that the introduction of prestressed technology into the top beam improved the overall mechanical performance of the structure.The overall arrangement of prestressing tendons was consistent,and the force transmission mode was clear,which well solved the limitation control problems as crack developments and deformations for large-span column-free underground stations.