反对称Pratt桁架中斜腹杆受压大偏心N形圆钢管节点静力性能试验研究  

Experimental research on static behavior of big eccentric circular hollow section(CHS) N-joints with inclination brace under compression in anti-symmetrical Pratt truss

作　　者：陈誉[1] 刘飞飞[1] 

机构地区：[1]华侨大学土木工程学院,福建厦门361021

出　　处：《建筑结构学报》2012年第3期30-38,共9页Journal of Building Structures

基　　金：国家自然科学基金项目(51008133);大连理工大学海岸和近海工程国家重点实验室基金项目(LP0705);泉州市第一批技术研究与开发项目(重点项目)(2009Z48)

摘　　要：对反对称Pratt桁架中的斜腹杆受压大偏心N形圆钢管节点的静力性能进行了单调加载试验研究。实施了4个负向大偏心、4个正向大偏心和1个无偏心斜腹杆受压N形圆钢管节点静力试验。介绍了节点试验方案,考察了斜腹杆受压大偏心圆钢管节点破坏现象,给出了加载点荷载-端位移曲线、腹杆轴力-管壁变形曲线以及折算应变分布曲线,并分析了偏心率对节点承载力、刚度和延性的影响。研究结果表明:该节点可以作为理想铰接节点考虑;随着节点偏心率从-1.30增大到0,节点承载力逐渐提高,当偏心率为0时达到最大;节点转变成正偏心,偏心率增大到0.50时,随着偏心率增大,试件承载力逐渐减小;之后随着偏心率继续增大,承载力又有略微增大;虽然两种规范(GB 50017—2003《钢结构设计规范》、欧洲Eurocode 3)计算均值与试验值比较接近,且GB 50017—2003计算均值更接近试验值,但两种规范计算承载力的变化趋势均与试验结果不符。To research the static behavior of big eccentric circular hollow section N-joints with inclined brace under compression in antisymmetrical Pratt truss, four big negative eccentric specimens, four big positive eccentric specimens and one non-eccentric specimen were tested under monotonic loading. The test procedure, joint failure phenomenon, vertical jack load-displacement curves, axial force of brace-deformation of wall and strain distribution curves were presented. The effect of eccentricity on bearing capacity, stiffness and ductility of the joints was also studied. Results of these tests show that big eccentric CHS N-joints with inclined brace under compression can be regarded as hingejoint by comparing experimental result with theoretical value. From - 1.30 to 0 eccentricity joints, with the increase of eccentricity, the bearing capacity of joints increase. From 0 eccentricity to O. 50 eccentricity joints, the bearing capacity of joints reduces. Finally, with the increase of eccentricity, the bearing capacity of joints slightly increases. Although the calculated averages value of bearing capacity by Chinese code and Euro code are close to experimental result, calculated value of bearing capacity by Chinese code is closer to experimental result than Euro code. Trends of joint bearing capacity from calculation by the two codes are totally different from that of the experimental result.

关 键 词：反对称Pratt桁架 大偏心N形圆钢管节点 直腹杆受压 静力试验 静力性能 

分 类 号：TU392.3[建筑科学—结构工程] TU317.1