主管内填充混凝土对矩形钢管桁架抗弯刚度影响研究  

Research on influnce of chord concrete-inside on overall stiffness of rectangular hollow section steel tube truss girder

作　　者：刘君平[1] 刘永健[2] 

机构地区：[1]福州大学土木工程学院,福建福州350108 [2]长安大学桥梁与隧道陕西省重点实验室,陕西西安710064

出　　处：《建筑结构学报》2009年第S2期202-207,共6页Journal of Building Structures

基　　金：教育部新世纪优秀人才支持计划资助项目(NCET-06-0855);国家西部交通建设科技项目(2006318812112);交通部应用基础研究项目(2006319812130)

摘　　要：为研究主管内填充混凝土对矩形钢管桁架抗弯刚度的影响,进行了空钢管、仅受压主管内填充混凝土和拉压主管内均填充混凝土三种类型桁架的对比试验研究。试验研究结果表明,矩形钢管桁架结构节点变形较大,需考虑其对桁架整体变形的影响,主管内填充混凝土作用主要体现在受压主管上,内填混凝土使得受压主管本身抗弯刚度增大的同时,增大了桁架的整体抗弯刚度。针对规范没有矩形钢管结构刚度变形计算方面的规定,提出了矩形钢管桁架及主管内填充混凝土矩形钢管桁架结构变形的简化计算方法,对于空钢管桁架结构、仅受压主管内填充混凝土和拉压主管均内填充混凝土三种类型桁架,建议其变形可以按照理想杆系铰接模型计算,但应考虑节点变形影响,桁架变形放大系数分别取为1.15、1.15和1.20。最后根据试验结果探讨了受压主管内填充混凝土抗压刚度和抗弯刚度的取值。To study the bending stiffness of steel tubular truss and the effects of chord-filled concrete,tests on three trusses with rectangular steel tubes and circular steel tubes were carried out,the first was a hollow steel tubular truss,the second was a hollow steel tubular truss with concrete filled in the compression chord,and the third was a hollow steel tubular truss with concrete filled in both the compression and tension chords.The test results shows: the joints deformation contribute substantially to the overall deflection,which need to be considered in calculating the overall bending stiffness of the overall truss;the chord-filled concrete improves the rigidity of overall truss and reduces the deformation of the joints.The filled concrete in compression chord increases both the compressive stiffness of the chord and the truss.A simplified method to calculate deformation was recommended for the three trusses,where the ideal node connection model is adopted.The joint deformation is considered in the simplified method,and the lattice deflection amplification factor is taken to 1.15,1.15 and 1.20 respectively for the three trusses.Finally,according to test results,reasonable values of the compressive stiffness and bending stiffness of compression chords were discussed.

关 键 词：矩形钢管桁架 填充混凝土 抗弯刚度 节点变形 放大系数 刚度折减 

分 类 号：TU398.9[建筑科学—结构工程]