简支变连续梁湿接缝接头疲劳损伤试验  

Fatigue damage experiment for junction of wet-joint of bridges transforming from simply-supported into continuous beams

作　　者：胡铁明[1,2] 黄承逵[2] 陈小锋[2,3] 梁振宇[1] 

机构地区：[1]沈阳大学,辽宁沈阳110044 [2]大连理工大学,辽宁大连116024 [3]成都基准方中建筑设计事务所,四川成都610015

出　　处：《土木工程学报》2010年第10期36-44,共9页China Civil Engineering Journal

基　　金：辽宁省交通厅科研重点项目(200514)

摘　　要：通过对简支梁转变的连续梁进行疲劳试验,分析构造钢筋与湿接缝接头疲劳性能的关系。试验包括1根连续梁静载试验和3根连续梁疲劳试验,其中3根疲劳试验梁湿接缝接头处配置不同数量的构造钢筋,配筋率分别为0、0.27%和0.61%。分析配置构造钢筋可避免湿接缝接头剪切疲劳破坏的机理及构造钢筋配筋率与抗弯钢筋应力幅和结构疲劳刚度损失的关系。构造钢筋不但可提高湿接缝接头的抗剪疲劳性能,而且可间接降低中支座和跨中钢筋的应力幅度,提高湿接缝接头的疲劳抗裂性能和降低结构刚度疲劳损失等。试验结果表明,构造钢筋配筋率与湿接缝接头抗剪疲劳性能成正比关系,亦即配筋率越低,原简支梁端头与湿接缝的结合面承担的剪切应力越大,越容易发生剪切疲劳破坏。建议在工程应用中,湿接缝接头宜设计配筋率不少于0.3%的构造钢筋。Through fatigue test of continuous beams transformed from simply-supported beams,the fatigue relationship between structural reinforcement and junction of wet-joint was analyzed.There were static load test of one continuous beam and fatigue tests of three continuous beams.Different structural reinforcements was employed in the junctions of wet-joints for the fatigue test,with reinforcement ratios of 0,0.27% and 0.61%,respectively.The theory that the junction of wet-joint could avoid shear fatigue failure by using structural reinforcement and the relationships between structural reinforcement ratio,bending reinforcement stress amplitude and structure fatigue rigidity loss were analyzed.Structural reinforcement may increase shear fatigue and anti-cracking capabilities,reduce stress amplitude of middle support and middle span reinforcement indirectly and decrease structure fatigue rigidity loss.The experimental results show that structural reinforcement ratio and shear fatigue capability of junction of wet-joint are direct proportionately related,which means when reinforcement ratio is lower,the shear stress in the joint surface of simply-support beam end and wet-joint is larger and shear fatigue damage may occur more easily.It is suggested that structural reinforcement ratio of junction of wet-joint should be no less than 0.3%.

关 键 词：连续梁 湿接缝 疲劳 损伤 构造钢筋 

分 类 号：TU375[建筑科学—结构工程]