混凝土非均匀性对超声波衰减作用的模拟分析  

Simulation Analysis of the Attenuation Effect of Random Inhomogeneity of Concrete on Ultrasonic Wave

作　　者：张文亮 辛公锋 宋雷[3] 龙关旭 ZHANG Wen-liang;XIN Gong-feng;SONG Lei;LONG Guan-xu(Shandong Hi-speed Group Innovation Research Institute,Jinan 250098,China;Shandong Key Laboratory of Highway Technology and Safety Assessment,Jinan 250098,China;State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining&Technology,Xuzhou 221116,China)

机构地区：[1]山东高速集团有限公司创新研究院,济南250098 [2]山东省高速公路技术和安全评估省级重点实验室,济南250098 [3]中国矿业大学深部岩土力学与地下工程国家重点实验室,徐州221116

出　　处：《科学技术与工程》2022年第21期9044-9053,共10页Science Technology and Engineering

基　　金：国家自然科学基金(41974164)。

摘　　要：为深入了解超声波在混凝土中的衰减特征和混凝土随机非均匀性的对应关系,首先,基于数字图像处理技术以混凝土骨料的含量、粒径为变量,建立了混凝土的数字模型;其次,引入Kelvin-Voigt本构关系表征超声波传播过程中的黏弹性;再次,应用谱比法分别测量了骨料和水泥砂浆的品质因子参量,并将其引入超声波控制方程;最后,在此基础上采用交错网格有限差分方法模拟了超声波在混凝土中的传播,并从能量和频率角度分析了骨料粒径、骨料含量、水泥砂浆波速和品质因子等随机参数对混凝土中超声波传播的影响。研究结果表明:超声波散射衰减对混凝土随机性最为敏感,是造成超声波能量衰减的主要衰减模式;黏弹性虽然会进一步造成能量的衰减,但是相比于散射,其影响可以忽略;对混凝土进行超声波无损检测的建议入射频率为50~100 kHz。研究为建立混凝土性能特征和超声波传播参数之间的映射关系提供了有益参考。To get a further insight into the corresponding relationship between ultrasonic attenuation characteristics in concrete and the concrete random inhomogeneity,firstly,based on digital image processing technology,the digital model of concrete structure was established by taking the content and particle size of aggregate as variable.Secondly,Kelvin-Voigt constitutive relation was introduced to characterize the viscoelasticity of concrete during ultrasonic wave propagation.Thirdly,the quality factors of aggregate and cement mortar measured by spectral ratio method and other measured parameters were fed into the ultrasonic control equation.Finally,the propagation of ultrasonic wave in concrete was simulated by staggered grid finite difference method.The influences of random parameters such as aggregate particle size,aggregate content,cement mortar wave velocity and quality factors on ultrasonic wave propagation in concrete were analyzed from the perspectives of energy and frequency.The results show that ultrasonic scattering attenuation is most sensitive to the randomness of concrete and is the main contribution of ultrasonic energy attenuation.Although the effect of viscoelasticity can be ignored,it will cause further attenuation compared with the scattering energy.The recommended incidence frequency for ultrasonic nondestructive testing of concrete structures is 50~100 kHz.The research provides a useful reference for establishing the mapping relationship between concrete properties and ultrasonic propagation parameters.

关 键 词：混凝土 随机非均匀性 超声波衰减 黏弹性 

分 类 号：P631[天文地球—地质矿产勘探]