基于压电传感器的混凝土空洞缺陷发展与修复监测试验研究  

Experimental study on concrete damage development and repair monitoring based on piezoelectric sensor

作　　者：杨俊涛 左文建 张文龙 姜珊[1] 杨涵笑 路国运[1] YANG Juntao;ZUO Wenjian;ZHANG Wenlong;JIANG Shan;YANG Hanxiao;LU Guoyun(Taiyuan University of Technology,Taiyuan 030024,China;China Railway No.3 Engineering Group Investment Co.,Ltd.,Taiyuan 030001,China)

机构地区：[1]太原理工大学土木工程学院,山西太原030024 [2]中铁三局集团投资有限公司,山西太原030001

出　　处：《混凝土》2024年第5期185-192,共8页Concrete

基　　金：国家自然科学基金面上项目(12172244);山西省自然科学基金(201901D111089)。

摘　　要：为监测混凝土结构服役期间其空洞缺陷的发展情况、缺陷修复后混凝土的缺陷程度并判定相应的抗压强度,探索一种基于应力波的监测方法:将两枚压电传感器粘贴在混凝土试件表面,一枚作为致动器,另一枚作为传感器,利用信号源产生电压信号激励致动器产生应力波,同时测量试件在不同空洞缺陷直径下及缺陷修复后传感器的输出电压,引入输出电压的特征值,之后测试相应试块的抗压强度,建立特征值与混凝土抗压强度间的定量关系评价混凝土力学性能。通过有限元模型研究了混凝土在不同直径的空洞缺陷下应力波的传播特性,证明了幅值与相位表征混凝土缺陷程度的可行性,由此提出基于波飞行时间的损伤参数和基于幅值的能量指数评价混凝土缺陷状态。最后设计了混凝土空洞缺陷发展与修复监测试验,采用扫频信号和脉冲信号对试块进行监测并提取特征值(能量指数、损伤参数)评价混凝土缺陷修复前后的缺陷状态及抗压强度,验证了该方法的可行性并给出了不同激励信号的适用条件。In order to monitor the cavity defect development of concrete structure during service,the defect degree of concrete after defect repair and determine the corresponding compressive strength,it explores a monitoring method based on stress wave two piezoelectric sensors are pasted on the surface of concrete specimen,one is used as actuator,the other as sensor,and the signal source is used to generate voltage signal to excite the actuator to generate stress wave.At the same time,measure the output voltage of the sensor under different cavity defect diameters and after defect repair,introduce the characteristic value of the output voltage,then test the compressive strength of the corresponding test block,establish the quantitative relationship between the characteristic value and the compressive strength of concrete,and evaluate the mechanical properties of concrete.Through the finite element model,the propagation characteristics of stress wave under different cavity defect diameters are studied,and the feasibility of characterizing the degree of concrete defects by amplitude and phase is proved.Therefore,the damage parameter based on time of flight and the energy index based on amplitude are proposed to evaluate the state of concrete defects.Finally,the concrete cavity defect development and repair monitoring test is designed.The frequency sweep signal and pulse signal are used to monitor the test block and extract the characteristic values(energy index and damage parameters)to evaluate the defect status and compressive strength before and after the concrete defect repair.The feasibility of this method is verified and the applicable conditions of different excitation signals are given.

关 键 词：压电传感器 混凝土缺陷 混凝土修复 抗压强度 频段能量谱 波飞行时间 

分 类 号：TU528.07[建筑科学—建筑技术科学]