细观尺度下表面波法检测混凝土表面裂缝深度研究  

Study on detection of concrete surface crack depth using surface wave method at a meso-scale

作　　者：孙林远 黄昊[1,2] 陈康 甄理 陈改新[1,2,3] SUN Linyuan;HUANG Hao;CHEN Kang;ZHEN Li;CHEN Gaixin(China Institute of Water Resources and Hydropower Research,Beijing 100038,China;China Institute of Water Resources and Hydropower Research State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,Beijing 100038,China;Key Laboratory of Engineering Materials of Ministry of Water Resources,Beijing 100038,China)

机构地区：[1]中国水利水电科学研究院,北京100038 [2]流域水循环模拟与调控国家重点实验室,北京100038 [3]水利部水工程材料重点实验室(筹),北京100038

出　　处：《水利学报》2024年第8期942-954,共13页Journal of Hydraulic Engineering

基　　金：中国水科院基本科研业务费项目(SM0145B042021)。

摘　　要：基于表面波截止频率检测混凝土表面裂缝深度是一种有效的无损检测方法。目前通常使用频率透射比法来识别截止频率,但该方法受混凝土细观结构影响较大,识别效果较差。为提高截止频率的识别精度,本文提出了多道信号相移频散分析法,开展了表面波检测均匀介质和混凝土细观模型表面裂缝深度的有限元模拟,通过对比研究频率透射比法和多道信号相移频散分析法的检测机理和识别效果,给出了截止频率的识别标准,最后分析了骨料、孔隙率和检测频率对多道信号相移频散分析法的影响。研究结果表明,多道信号相移频散分析法的识别效果较好,且不受细观结构和缝厚比的影响;骨料粒径、含量和弹性模量的变化基本不影响该方法对截止频率的有效识别;当表面波波长小于构件厚度且孔隙率不超过4%时,该方法仍具备较好的识别效果。本研究可为实际工程中混凝土表面裂缝深度的定量检测提供理论基础。Detecting the depth of concrete surface cracks based on the R-wave cutoff frequency is an effective non-destructive testing method.Currently,the frequency transmission ratio method is commonly used to identify the cutoff frequency;however,this method is greatly affected by the concrete’s meso-structure,leading to suboptimal identification results.To enhance the accuracy of cutoff frequency identification,this paper proposes the multi-channel signal phase shift dispersion analysis method.Finite element simulations were conducted to detect the depth of surface cracks in uniform media and concrete meso-models using R-waves.The detection mechanisms and identification effects of the frequency transmission ratio method and the multi-channel signal phase shift dispersion analysis method were compared and studied.Standards for identifying the cutoff frequency were provided,and the effects of aggregate size,porosity,and detection frequency on the multi-channel signal phase shift dispersion analysis method were analyzed.The research results indicate that the multi-channel signal phase shift dispersion analysis method has better identification effects and is not affected by the meso-structure and the crack thickness ratio.Changes in aggregate size,content,and elastic modulus basically do not affect the method’s effective identification of the cutoff frequency.When the R-wave wavelength is less than the thickness of the component and the porosity does not exceed 4%,the method still exhibits good identification effects.This study can provide a theoretical basis for the quantitative detection of concrete surface crack depth in practical engineering.

关 键 词：混凝土表面裂缝深度 细观结构 截止频率 频率透射比法 相移法频散分析 

分 类 号：TV698.15[水利工程—水利水电工程]