负载下工形截面压弯钢构件焊接加固的承载性能分析  

Analysis of Load-Carrying Behavior of I Section Steel Beam-Columns Strengthened by Welding Under Load

作　　者：蒋立[1,2] 王元清[3] 戴国欣[1,2] 张天申[3] 石永久[3] 

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]山地城镇建设与新技术教育部重点实验室(重庆大学),重庆400045 [3]土木工程安全与耐久教育部重点实验室,清华大学土木工程系,北京100084

出　　处：《天津大学学报（自然科学与工程技术版）》2015年第B07期60-66,共7页Journal of Tianjin University：Science and Technology

基　　金：《钢结构加固设计规范》国家标准管理组科研专项课题资助项目(2013-01)

摘　　要：为研究初始负载对负载下焊接加固工字形压弯钢构件承载性能的影响,采用通用有限元分析软件ANSYS建立有限元模型,结合生死单元法并考虑了体壳耦合、接触及摩擦等,对不同初始负载下焊接加固的4个工字形压弯钢柱进行了模拟分析.研究了在受力过程中构件的荷载-位移关系、塑性渗透、加固后失稳破坏模式及稳定承载力,通过有限元结果与相应试验结果进行对比验证了试验中摩擦存在的影响以及有限元方法的可靠性,并进而与规范计算结果对比考察了现有设计方法.结果表明:初始负载越大,压弯构件的极限承载力和原构件边缘屈服承载力均越低,且初始几何缺陷能够影响极限承载力;现有规范方法不能反映初始负载对压弯构件承载力的影响而偏不安全.To investigate the influence of initial load on load-carrying behavior of steel beam-columns strengthened by welding under load, the finite element models were established by applying the general finite element analy- sis（FEA） software ANSYS. Based on the birth-death element method, body-shell element coupling, contact and friction were also examined. Four I section steel beam-columns strengthened by welding under different initial loads were simulated. The load-displacement relationship and plastic penetration of specimens during the load process were discussed, so were the buckling mode and stability bearing capacity after strengthening. By comparing the FEA re- suits and test results, the influence of the existing friction in test and the effectiveness of the FEA method were veri- fied. And by follow-up comparison with the coded calculation results, the present design method was explored. Re- suits show that the higher initial loads, the lower ultimate capacity and original margin yield capacity of beam- columns; and that initial geometric imperfections impact ultimate capacity. The influence of initial load on capacity cannot be reflected in the present code method, and thus indicating potential risk.

关 键 词：钢结构加固 工形截面 压弯构件 负载焊接 承载性能 有限元分析 

分 类 号：TU391[建筑科学—结构工程]