核心受压玄武岩纤维管约束混凝土圆柱的声发射特性  

ACOUSTIC EMISSION CHARACTERISTICS OF CIRCULAR CONCRETE COLUMNS CONFINED BY BFRP TUBE UNDER CORE CONCRETE IMPOSED AXIAL LOADS

作　　者：王慧青 张大山[2] 张建春 黄栋强 WANG Huiqing;ZHANG Dashan;ZHANG Jianchun;HUANG Dongqiang(College of Architecture and Civil Engineering,Xiamen Institute of Technology,Xiamen 361021,China;College of Civil Engineering,Huaqiao University,Xiamen 361021,China)

机构地区：[1]厦门工学院建筑与土木工程学院,福建厦门361021 [2]华侨大学土木工程学院,福建厦门361021

出　　处：《工业建筑》2021年第5期196-203,共8页Industrial Construction

基　　金：福建省中青年教师教育科研项目(JAT190949);福建省自然科学基金项目(2019J01051);厦门工学院校级科研项目(KYT2019011)。

摘　　要：为能够实时监测约束混凝土构件的损伤过程和建立能够预测破坏的预警指标,开展了4个玄武岩纤维增强聚合物(Basalt Fiber Reinforced Polymer,简称BFRP)管约束混凝土圆柱轴心受压下的声发射信号测试试验,并进行了声发射参数的特性研究、关联分析和损伤计算。通过试验,研究不同直径(壁厚相同)、是否配筋等参数对BFRP管约束混凝土圆柱在受力过程中的声发射特征参数变化规律的影响。研究表明:BFRP管约束混凝土圆柱在不同的受力阶段会表现出不同的声发射信号变化特征;在壁厚相等时,直径小的BFRP管约束圆柱,在加载前期的损伤发展相对较慢,而在中后期则会损伤加快并较早破坏;由RA-AF关联分析可知,混凝土内部的张拉裂纹主要出现在弹性阶段,而剪切裂纹主要出现在弹塑性阶段;内部有、无配筋的约束构件均会发生脆性破坏,但是内部配置钢筋会改变约束构件在加载过程中的声发射信号变化规律,从而可以选择某个参数曲线的典型变化特征作为该类构件发生破坏前的预警提示。In order to monitor the damage process of confined concrete elements in buildings and establish an early-warning index to predict the failure status in real-time,four experimental tests of circular concrete columns confined by BFRP(Basalt Fiber Reinforced Polymer)tube(CCCBT)were carried out to collect the acoustic emission signals during the loading condition.Meanwhile,the characteristics of acoustic emission parameters,correlation analysis,and damage index calculation were conducted based on the experimental data.The variation of acoustic emission characteristic parameters of CCCBTs,which had different diameters and reinforcement ratios(with the same pipe thickness),was studied through experiments.It was indicated that the CCCBTs presented different characteristics of acoustic emission at different loading stages.The damage development of CCCBTs with smaller diameter(but with identical thickness)was slower relatively at the early loading stage,and then became faster until that the failure appeared.Through the RA-AF correlation analysis,it was concluded that most of tensile cracks formed at the elastic stage,while the shear cracks appeared mainly at the elastic-plastic stage.All the CCCBTs,whether having inner steel reinforcements or not,were brittle failure mode.However,the CCCBTs with inner steel reinforcements altered the variational features of acoustic emission signals.For this reason,some typical variational features could be chosen to predict the hazard ahead of the failure.

关 键 词：BFRP管 约束混凝土 圆柱 声发射 内部损伤 

分 类 号：TU37[建筑科学—结构工程]