疲劳荷载作用下部分预应力混凝土梁残余性能试验研究  

Experimental study on the residual performance of partially prestressed concrete beams under fatigue loading

作　　者：韩基刚 HAN Jigang(Research and Development Center on Road and Bridge Diagnosis&Maintenance Technology Ministry of Transport,Liaoning Provincial Transportation Planning and Design Institute Co.,Ltd.,Shenyang 110166,China)

机构地区：[1]辽宁省交通规划设计院有限责任公司公路桥梁诊治技术交通运输行业研发中心,沈阳110166

出　　处：《建筑结构》2021年第4期96-100,70,共6页Building Structure

基　　金：辽宁省交通厅科技计划项目(201913);浙江省交通厅科技计划项目(2020039)。

摘　　要：为研究部分预应力混凝土(PPC)梁在疲劳荷载作用后的残余性能,制作8根试验梁(分为H1和H2组,各4根),每组选取1根作为参考梁开展静载试验,其余进行等幅疲劳试验,重点分析梁体累积残余变形和非预应力钢筋残余应变的演化规律及影响因素。试验结果表明:所有疲劳试验梁的破坏模式为非预应力钢筋的疲劳断裂;在疲劳荷载作用下,梁体残余变形、非预应力钢筋残余应变均呈现出"三阶段"变化规律,其中残余变形大小与荷载水平和配筋率密切相关,而残余应变受其影响并不显著,主要受钢筋周围混凝土微裂缝闭合状态及受压区混凝土疲劳损伤程度影响较大。An experimental study was conducted to investigate the residual performance of partially prestressed concrete(PPC) beam. Eight PPC beams were made and divided into H1 and H2 groups, each group containing one control beam under static loading and three beams under constant amplitude fatigue loading. The evolution law and its influencing factors of cumulative residual deformation of beams and residual strain of the non-prestressed reinforcement have been analyzed. The results of the study indicate that the failure modes for all of the beams fatigue testing are fatigue fracture of the non-prestressed reinforcement;under the fatigue loading, the growth processes of residual deformation and residual strain of the non-prestressed reinforcement are characterized by three stages. The residual deformation is closely related to the load level and reinforcement ratio, but it has less effect on the residual strain. This strain is more affected by the closed state of microcracks in concrete around the reinforcement and fatigue damage degree in the concrete compressive zone.

关 键 词：部分预应力 疲劳荷载 残余变形 非预应力钢筋 残余应变 

分 类 号：TU378.8[建筑科学—结构工程] U446.1[建筑科学—桥梁与隧道工程]