钢筋混凝土梁声发射检测参数设置和受力特征试验研究  

Experimental research on the acoustic emission detecting parameters and mechanical behaviors for reinforced concrete structure

作　　者：门进杰[1] 朱乐[1] 李欢[1] 王晓丹[1] 

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055

出　　处：《西安建筑科技大学学报（自然科学版）》2015年第6期793-798,共6页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：国家自然科学基金项目(51008244;51178380);陕西省自然科学基础研究计划基金项目(2015JM5173;2014JQ7245;2014KJXX-67)

摘　　要：为了建立声发射参数与钢筋混凝土梁受力特征之间的关系,进行了钢筋混凝土梁的四点弯曲试验和声发射测试试验.通过预加载和断铅试验,给出了适用于钢筋混凝土梁的门槛值确定方法、时间参数(峰值定义时间、撞击定义时间和撞击闭锁时间)确定方法、声发射波速的测定方法,以及相应的测试结果.通过四点弯曲试验和声发射测试试验,得到了振幅、振铃计数、能量和上升时间等声发射参数随荷载的变化关系,揭示了利用上述声发射参数表征钢筋混凝土梁受力特征的规律和方法.基于声发射参数,通过计算得到了试件在初始开裂和屈服时的裂缝分布情况,与试验结果相比,在裂缝数量和裂缝位置上,均吻合较好.Four-point bending test and AE test of a RC beam were conducted in order to capture the relations between acoustic emission （AE） parameters and mechanical characteristic for reinforced concrete （RC） structure. Procedures to determine the thresh- old level, time parameters （PDT, HDT, HLT） and wave velocity for RC beam were demonstrated by AE pre-test and Pencil Lead Breaks （PLBs）. Relations between AE parameters, such as amplitude, ringdown count, energy and rise time, and the applied load were obtained based on four-point bending test and AE test. Then the method to assess the mechanical behaviors of RC beams by these AE parameters were established. In addition, the crack locations, when the beam began to crack and to yield, were calculated by AE parameters. The results show close correlation in the calculated crack location and crack amount with the bending test.

关 键 词：声发射 钢筋混凝土结构 无损检测 断铅试验 基于参数的分析 

分 类 号：TU375[建筑科学—结构工程]