钢板组合梁桥主梁与竖向加劲肋连接细节疲劳应力特征  

Fatigue stress characteristics of connection details between main girder and vertical stiffener in steel plate girder bridge

作　　者：刘青茹 吉伯海[1] 姚悦[1] 傅中秋[1] LIU Qingru;JI Bohai;YAO Yue;FU Zhongqiu(College of Civil and Transportation Engineering, Hohai University, Nanjing 210098, China)

机构地区：[1]河海大学土木与交通学院,江苏南京210098

出　　处：《南京工业大学学报（自然科学版）》2021年第3期381-389,共9页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：国家重点研发计划(2017YFE0128700);江苏省交通运输科技与成果转化项目(2019Y69)。

摘　　要：为研究钢板组合梁桥主梁与竖向加劲肋连接细节的疲劳应力特征,通过建立四跨连续钢板梁桥整体有限元模型以及无横梁处、小横梁处主梁两种节段有限元模型,提取疲劳荷载移动下的两主梁竖向位移差,对比分析无横梁与小横梁两种情况主梁相对竖向位移的差异及原因,进一步提取主梁与竖向加劲肋连接细节应力,讨论无横梁与小横梁两种情况主梁与竖向加劲肋连接细节疲劳应力的差异,得到钢板组合梁桥主梁与竖向加劲肋连接细节的疲劳易损部位。结果表明:车辆荷载对主梁构造应力顺桥向影响范围为荷载所在跨范围内,横桥向对无横梁处主梁的竖向位移差影响效果更大;无横梁处主梁在主梁腹板与下翼缘连接焊缝的焊趾处有较大拉应力,而小横梁处主梁在竖向加劲肋与主梁腹板围焊端部的焊趾处产生更大的拉应力。In order to study the fatigue stress characteristics of the connection details between the main girder and the vertical stiffener of the steel plate girder bridge,the vertical displacement difference of the two main girders under fatigue load movement is extracted,by establishing integral finite element models of a four-span continuous steel plate girder bridge,and the two main girder segment of non-beam and the small cross-beam.The vertical displacement difference in above cases and reasons of inducing the differences are compared and analyzed.By analyzing the stresses of the connection details,the possible location of fatigue failure is found.Results show that in longitudinal direction,vehicle load has impact on the structural stress of the main girder within the span,whereas,in transverse direction,it has a greater effect on the difference of vertical displacement of the main girder with no cross-beam.For main girder without beams,large tensile stress occurs at the weld toe of connection weld,meanwhile,for main girder with small cross-beam,greater tensile stress generates at the welding toe of surrounding weld end between vertical stiffener and main girder web.

关 键 词：钢板组合梁桥 疲劳应力 应力特征 车辆荷载 竖向位移 

分 类 号：U448.36[建筑科学—桥梁与隧道工程]