双层复合桁架桥复合桁架与钢桁架结合段连接性能试验研究  

Experimental study of hybrid joint segment for cable-stayed composite truss bridge with double deck

作　　者：辛灏辉[1] 刘玉擎[1] 马骉[2] 

机构地区：[1]同济大学桥梁工程系,上海200092 [2]上海市政工程设计研究总院(集团)有限公司,上海200092

出　　处：《建筑结构学报》2013年第S1期45-51,共7页Journal of Building Structures

摘　　要：为探究双层复合桁架桥混合梁复合桁架与钢桁架结合段主要构件的应力分布、传力途径及弦杆承载比例,选取复合桁架与钢桁架在弦杆处的连接局部构造进行研究,以1∶2.5为缩尺,对弦杆结合段进行了局部模型试验。试验结果表明:钢板、钢筋和混凝土荷载-应力曲线基本保持线性关系,加载力从1.0倍设计荷载提高至1.7倍设计荷载,钢板、钢筋及混凝土应力增加幅值均接近70%,表明试件始终保持弹性工作状态,尚未发生塑性变形;各构件最大应力远小于允许应力;钢板、混凝土及钢筋应力沿纵向的变化趋势;在弦杆结合段中,钢承担约20%的荷载,混凝土承担约80%的荷载,混凝土在承担荷载中起主要作用。在1.7倍设计荷载作用下,结合段传力合理,安全可靠,且具有较高的安全储备。In order to investigate stress distribution,force transfer and the ratio of loads carried by the joint segment of steel truss and composite truss,a model test with the scale of 1∶ 2.5 was conducted.The results show that the loadstrain relationships of steel plate,concrete and rebar of the joint segment remain linear,and the stress of each component can be increased by 70% when the load is increased from 100% design load to 170% design load,indicating the test specimen is under elastic state.The maximum stress in the structure is less than the material allowable strength.The trends of stress variation for steel plate,concrete and rebar are presented in this paper.The ratio of load resisted by the shaped steel chord is about 20% of the total load resisted by the composite chord.The load is mainly resisted by the concrete chord.Therefore,the force transfer of the joint segment is reliable and the composition details are rational under 170% of the design load.

关 键 词：双层复合桁架桥 弦杆结合段 静力试验 连接性能 

分 类 号：U448.216[建筑科学—桥梁与隧道工程]