岩土随机介质中的超声波场及其相控阵检测关键技术

项目名称： 岩土随机介质中的超声波场及其相控阵检测关键技术

项目编号： No.41474122

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 天文学、地球科学

项目作者： 宋雷

作者单位： 中国矿业大学

项目金额： 80万元

中文摘要： 作为典型的隐蔽工程，地下结构健康检测广受重视。随深度增加，地下结构的用钢量增加、厚度增大。尤其在深部地下工程中，普遍采用多排钢筋或钢板混凝土等结构形式，浅部地下工程检测中中常用的物探方法不再适用。超声相控阵具有高精度、高检出率、高效率的特点，可实现动态聚焦，在医学诊断、金属结构检测等领域应用广泛。然而，岩土介质具有显著的随机性，高频率的超声波将在其中出现频散导致信噪比降低，常规的超声相控阵设备在岩土工程检测中并不适用。本项目拟从岩土介质的声学参数测试出发，建立岩土随机介质模型；通过数值模拟和模型试验，获得岩土随机介质中超声波场的传播规律，确定适与地下工程检测的超声波频带；进而，研发相对低频的、适于地下工程检测的超声相控阵设备，并通过模型试验和现场实测，获得地下结构中典型缺陷的相控阵图像特征。本项目采用物探手段解决深部地下工程的重大技术难题，有典型的学科交叉特点和深部地下特色。

中文关键词： 地下工程；岩土随机介质；随机超声波场；超声相控阵；无损检测

英文摘要： As a typical concealed engineering, the Non-Destructive Testing(NDT) of underground structures has taken widely attentions. With the depth increase, the steel quantity and the thickness of the underground structures have also increased. Especially in the deep underground structure, the widely used multi-rebar reinforced concrete and steel-concrete structure in the deep underground engineering have limited the application of the Geophysical methods used in the the common underground engineering. It was needed to develop a new NDT method via ultrasonic wave. Ultrasonic Phased Array(UPA) has the characteristics of high precision, high detection rate, high efficiency, and can realize dynamic focusing. It was widely applied in medical diagnosis, metal structure detection et al. However, because of the significant stochastic vibration of the geotechnical media, frequency dispersion would be inevitable when the high frequency ultrasonic wave propogated in the stochastic geotechnical media, and the Signal to Noise Ratio (SNR) would be decreased largely. So,the conventional UPA device could not be applied directly in the NDT of geotechnical engineering. In this project,through the acoustic parameters testing of geotechnical media, geotechnical stochastic media model would be established ; Based on the stochastic model, through numerical simulation and exprimental test, the the ultrasonic wave field in geotechnical random medium would be studied ;Then,UPA with suitble lower frequency signalul would be developed,and the model experiment test and field exploration would be carried out to master the characteristics of typical defects in underground structure.In this project, geophysical methods would be developed to solve the major technical problems of deep underground engineering, and the interdisciplinarity and underground engineering characteristics are noticeable.

英文关键词： Underground Engineering;Geotechnical Stochastic media;Stochastic ultrasonic wave field;Ultrasonic Phased Array(UPA);Non-Destructive Testing(NDT)