无切口钢-UHPC组合桥面纵肋-横隔板接头疲劳性能  

Fatigue Behavior of Rib-to-diaphragm Joint of Steel-UHPC Composite Bridge Deck without Cutout

作　　者：向泽 祝志文[2] XIANG Ze;ZHU Zhi-wen(School of Urban and Rural Construction,Shaoyang University,Shaoyang Hunan 422000,China;School of Engineering,Shantou University,Shantou Guangdong 515063,China;School of Civil Engineering,Hunan University,Changsha Hunan 410082,China)

机构地区：[1]邵阳学院城乡建设学院,湖南邵阳422000 [2]汕头大学工学院,广东汕头515063 [3]湖南大学土木工程学院,湖南长沙410082

出　　处：《公路交通科技》2021年第8期83-92,共10页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金项目(51878269)。

摘　　要：为解决正交异性钢桥面纵肋-横隔板接头疲劳开裂问题,根据正交异性钢桥面构造特点,提出了一种疲劳性能良好的新型无切口正交异性钢-UHPC组合桥面,能简化制造工艺,提高经济性能。基于ANSYS数值分析平台建立双尺度有限元模型,采用欧洲规范疲劳荷载模型III开展纵桥向移动加载,获得了纵肋-横隔板接头在3种典型横向位置下的轮载热点应力响应曲线。结合轮载作用下的应力云图和变形图,揭示了构造细节力学机理,评估了疲劳性能,并探讨了构造参数的影响。应力响应曲线表明:纵肋-横隔板接头在轮载作用下的应力响应以受压为主,局部效应显著,纵桥向应力影响线短,因而可根据轮载应力响应曲线识别轴组中的单轴。应力云图和变形图表明:构造细节在轮载作用下出现了显著应力集中,因新型桥面横隔板截面削弱较小,横隔板侧应力梯度小于纵肋侧。纵肋-横隔板接头应力最大点均不在纵肋正底部位置,而是与纵肋中心线成一定角度。由于纵肋-横隔板接头与面板距离较大,UHPC层和面板厚度对其疲劳性能改善并不明显。增加横隔板厚度能减小横隔板侧应力幅,但会增加纵肋侧应力幅,横隔板厚度可取10 mm。增大纵肋腹部厚度可有效减小纵肋侧应力幅,16 mm的纵肋腹部厚度可使得纵肋-横隔板接头实现无限疲劳寿命。To address the cracking problem of rib-to-diaphragm(RD)joint in orthotropic steel bridge deck(OSBD),based on the structural characteristics of OSBD,a novel orthotropic steel-UHPC composite bridge deck without cutout and has good fatigue behavior,which can simplify the manufacture process and enhance economic performance,is proposed.The 2-scale finite element model is built based on ANSYS numerical analysis platform,and the moving loading in bridge longitudinal direction is exerted by using the fatigue load model III in Eurocode 3 specifications,and the hot-spot stress response curves of RD joint in 3 typical bridge transverse directions are obtained.Based on the stress contour and deformation pattern under wheel loads,the mechanical mechanism of structural details is revealed,the fatigue performance is assessed,and the influence of structural parameters is discussed.The stress response curves show that the stress response of the RD joint under wheel loads is dominated by compression,the local effect is significant,the stress influence line in bridge longitudinal direction is short,hence the single axle in the axle group can be identified according to the wheel load stress response curve.Both the stress contour and deformation pattern indicate that(1)there is obvious stress raiser at the structural detail have under wheel load,and the stress gradient at diaphragm side is smaller than that at rib side due to less section weakening of the diaphragm in the novel bridge deck;(2)the position with maximum stress of the RD joint is not at the rib bottom,but at a certain angle to the center line of the rib;(3)since the RD joint is a little far from the deck,the improving effect of the thicknesses of both the UHPC layer and deck is not significant on its fatigue performance;(4)increasing the diaphragm thickness can reduce the stress range at diaphragm side but will also increase the stress range at rib side,and the diaphragm thickness of 10 mm is feasible;(5)increasing the thickness at the rib belly can significantly reduc

关 键 词：桥梁工程 正交异性桥面 有限元法 疲劳 纵肋-横隔板 应力幅 

分 类 号：U448.36[建筑科学—桥梁与隧道工程]