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第 40 卷 第 3 期                                                                       Vol. 40, No. 3
             2021 年 5 月                          Journal of Applied Acoustics                      May, 2021

             ⋄ 研究报告 ⋄


              混凝土中的声发射波速特性及其在源定位中的应用                                                                     ∗



                                      李冬雪     1†   杨 康     2   何兆益     1   周翰林     2

                                            (1  重庆交通大学交通运输学院        重庆   400074)
                                            (2  重庆交通大学土木工程学院        重庆   400074)

                摘要:利用声发射技术监测受载混凝土裂缝发展特征的首要任务是对声发射源的准确定位。为了解混凝土中
                声发射波速特性,提高声发射源定位精度,该文开展了一系列室内试验,构建了考虑衰减现象的声发射波速
                修正模型,优化建立了基于修正波速的区域穷举定位法。结果表明:水灰比越小,基准波速越大,波速随距离
                的衰减越大。骨料粒径越大,基准波速越大,波速随距离的衰减越大。直线距离小于 500 mm 时,可采用对数
                函数描述声发射波速与距离的定量关系,以此构建的波速修正模型满足工程精度要求。采用修正波速的区域
                穷举定位法对单轴压缩试验产生的裂缝进行定位时,定位点比时差定位法更接近裂缝实际位置,有效提高了
                定位精度。
                关键词:混凝土;声发射;波速特性;源定位
                中图法分类号: TU112.6           文献标识码: A          文章编号: 1000-310X(2021)03-0400-07
                DOI: 10.11684/j.issn.1000-310X.2021.03.011

                Acoustic emission wave velocity character in concrete and its application in
                                                  source localization


                                 LI Dongxue 1  YANG Kang   2  HE Zhaoyi 1  ZHOU Hanlin 2

                        (1 Chongqing Jiaotong University, College of Tranffic & Transportation, Chongqing, 400074, China)
                           (2 Chongqing Jiaotong University, School of Civil Engineering, Chongqing, 400074, China)

                 Abstract: The primary task of monitoring the development characteristics of concrete cracks under load by
                 acoustic emission technology is to accurately locate acoustic emission sources. In order to understand the
                 character of acoustic emission in concrete and improve the positioning accuracy of acoustic emission source, a
                 series of laboratory tests were carried out in this paper, a wave velocity correction model of acoustic emission
                 considering attenuation phenomenon was constructed, and a regional exhaustive positioning method based on
                 the corrected wave velocity was optimized. The results show that the smaller the water-cement ratio is, the
                 larger the reference wave velocity is and the larger the attenuation of the wave velocity is with the distance.
                 The larger the aggregate particle size is, the larger the base wave velocity is and the larger the attenuation of
                 the wave velocity is with the distance. When the linear distance is less than 500 mm, the logarithmic function
                 can be used to describe the quantitative relationship between acoustic emission wave velocity and distance, so
                 that the wave velocity correction model constructed can meet the requirements of engineering accuracy. The
                 location point is closer to the actual location of the crack than the time difference method, which can effectively
                 improve the location accuracy when using the zone exhaustion method with modified wave velocity to locate
                 the crack.
                 Keywords: Concrete; Acoustic emission; Wave velocity character; Localization

             2020-08-27 收稿; 2021-01-24 定稿
             国家重点研发计划项目 (2018YFB1600200)
             ∗
             作者简介: 李冬雪 (1983– ), 女, 黑龙江哈尔滨人, 博士, 高级工程师, 研究方向: 道路基础设施性能感知。
             † 通信作者 E-mail: lidongxue@cqjtu.edu.cn
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