矩形钢管混凝土大跨度带悬挑桁架的试验研究  

Experimental Study on Long-Span Concrete-Filled Rectangular Steel Tubular Truss with Cantilevers

作　　者：杨春[1] 蔡健[1] 陈国栋[1] 罗旗帜[2] 左志亮[1] 

机构地区：[1]华南理工大学土木与交通学院,广东广州510640 [2]佛山科学技术学院土木工程学院,广东佛山528000

出　　处：《华南理工大学学报（自然科学版）》2008年第3期128-133,共6页Journal of South China University of Technology(Natural Science Edition)

摘　　要：矩形钢管混凝土桁架结构形式能充分发挥钢管混凝土的受力性能,是一种适用于大跨度结构的结构形式.文中通过对两个大尺寸的大跨度带悬挑矩形钢管混凝土桁架和矩形钢管桁架模型对比试验,考察了该桁架结构的破坏形态、变形特点和承载性能.试验结果表明:填充混凝土的钢管混凝土桁架试件的刚度提高,变形减小,极限承载力也有所提高,填充混凝土可以有效防止钢管壁的局部屈曲,试件破坏受材料的强度控制;采用直接焊接节点连接的钢管桁架和钢管混凝土桁架中腹杆和弦杆在节点处的杆端弯矩较大,其对节点承载力的影响不可忽略,在设计中应加以考虑.Concrete-filled rectangular steel tubular （CFRST） truss is suitable for long-span structures because it possesses excellent mechanical properties due to the concrete-filled steel tube. In this paper, the experiments of two large specimens were performed to make a comparison between the CFRST truss with cantilever and the rectangular steel tubular （RST） truss. The destruction mode, deformation and ultimate strength of the CFRST truss were then investigated. Experimental results show that, as compared with the RST truss, the CFRST truss is of higher stiffness, ultimate strength and smaller deformation. The filled concrete can effectively prevent the steel tube from locally buckling, and the destruction mode of the specimens is controlled by material strength. The moments of the chord members and the web members at the joints where the members are connected by direct welding are quite large, so that the effect of the moments on the ultimate strength of the joints cannot be ignored in engineering design.

关 键 词：矩形钢管混凝土 桁架 大跨度 受力性能 

分 类 号：TU398[建筑科学—结构工程]