【作者】 薛云峰；

【导师】 何继善；

【作者基本信息】 中南大学 ， 地球探测与信息技术， 2007， 博士

【摘要】 本文在阅读大量国内外文献的基础上，研究了一套准确、经实践验证的混凝土防渗墙施工过程质量检测控制，成墙后垂直反射法、瞬变电磁法地面无损普查与少损层析成像详查相结合的混凝土防渗墙质量检测模式，并将研究成果应用于河北省黄壁庄水库副坝混凝土防渗墙质量控制及检测中，取得了良好的效果。为我国今后大量的混凝土防渗墙工程施工质量检测提供了技术保障。主要研究工作及成果如下：(1)对混凝土防渗墙施工过程中常规质量检测指标和检测方法进行分析总结，进一步规范化；针对施工规范及设计提出的混凝土防渗墙垂直度的要求，分析研究施工槽孔孔斜率的检测方法并论证叠加孔斜率方法检测孔斜的严格性和可行性；根据设计提出的混凝土防渗墙厚度的要求和相交圆的性质，分析研究Ⅰ、Ⅱ期槽孔最小套接厚度的检测指标和计算方法。(2)从弹性波传播的基本理论研究出发，推导了弹性波在类似混凝土防渗墙模型的二维垂向不均匀介质中传播的波动方程式；建立了混凝土防渗墙二维弹性薄板模型，研究弹性波在混凝土防渗墙中的传播、衰减、反射、透射规律及能量分配关系；从分辨率的概念出发，提出了垂直反射法检测混凝土防渗墙分辨率的内涵，对影响分辨率的因素进行了分析，推导出了缺陷层复合反射系数、可检测缺陷层极限厚度的表达式；建立了垂直反射法采样系统各环节之间的关系，研究分析了震源特性、接收传感器对测试结果的影响，提出了对测试仪器参数的要求及采集参数的选择原则。从理论、模型、分辨率、测试技术等方面，研究论证了垂直反射法检测混凝土防渗墙质量是一种实用、无损、效果明显的方法，作为一种质量普查方法是比较适宜的。(3)针对混凝土防渗墙的特征，进一步完善瞬变电磁法检测防渗墙的理论体系、数据处理程序以及现场观测系统；利用等效代换的方法建立了瞬变电磁响应的概念、方法以及瞬变电磁场的扩散规律，推导计算出全区视电阻率及视深度参数的计算公式，进行混凝土防渗墙的二维电阻率成像，提高了检测结果定量分析的水平。(4)分析总结了层析成像技术的发展及研究状况，检测混凝土防渗墙质量的物理基础及数学基础；归纳总结了各种射线追踪技术、及算法的优缺点，在此基础之上，编制层析成像直射线及弯曲射线正反演处理系统软件；依据混凝土防渗墙的特点，分别设计不同缺陷模型，进行正反演解析，确定了层析成像技术检测混凝土防渗墙缺陷的准确性、提出提高成像分辨率的措施；建立空洞模型，研究了层析成像最低分辨率的条件以及分辨能力与异常体尺寸、速度之间的关系，并用混凝土模型板试验验证了层析成像技术检测混凝土防渗墙缺陷的有效性；利用标准模块波速测试和抗压强度试验数据，建立了波速和混凝土强度之间的非线性回归方程，提高了层析成像检测混凝土防渗墙的定量化水平。更多还原

【Abstract】 Based on abundant reading of domestic and foreign documentations, thisarticle researches on quality inspection pattern for concrete cutoff wallcombined with quality inspection control, vertical reflection, on surfacenon-destructive reconnaissance by transient electromagnetic methods and fewdestructive tomographic imaging. The research achievement has been appliedin quality control and inspection for concrete cutoff wall in attached dam ofHuangbizhuang reservoir in Hebei province, and good results have beenachieved. All this provides technical guarantees for construction qualityinspection for future large numbers of concrete cutoff wall projects. The mainresearches and achievements are as follows:(1) Analyze and further formalize normal quality inspection index andinspection methods used in concrete cutoff wall construction; In accordancewith the verticality required by construction specification and design ofconcrete cutoff wall, test method for construction slot hole inclination areanalyzed and researched, the strictness and feasibility of hole inclinationinspection by stacked hole inclination method are demonstrated; Inspectionindex and calculation methods of minimum joint thickness of stageⅠ, stageⅡslot hole are analyzed based on design requirement of concrete cutoff wallthickness requirement and property of crossed circle.(2) Based on basic theory of elastic wave propagation, wave equation forpropagation of elastic wave in 2 dimension vertical inhomogeneous mediumof similar concrete cutoff wall model is developed. 2 dimension elastic sheetof concrete cutoff wall is established to research law and energy distributionrelations between propagation, attenuation, reflection and transmission ofelastic wave in concrete cutoff wall; Based on the concept of resolution, thecontent of vertical reflection method used to inspect concrete cutoff wallresolution is raised and factors will have influences on resolution are analyzed,expression of defective layer composite reflection factor and detectabledefective layer maximum thickness are developed; Relations between allsteps of sampling system of vertical reflection are build, the influence ofcentrum characteristics and receiving sensor on testing results are analyzed,therefore parameter requirements for testing instrument and parameter selection principle of collected parameters are raised. Based on the theory,model, resolution and testing technology, it is demonstrated that verticalreflection method used for testing of the quality of concrete cutoff wall is apractical, nondestructive and effective method and suitable for qualityreconnaissance.(3) In accordance with the characteristics of concrete cutoff wall, furthercomplete the theory system, data processing program and on situ observationsystem of transient electromagnetic method used in inspecting of cutoff wall;Concept and method of transient electromagnetic response and dispersion lawof transient electromagnetic field are established based on equivalentsubstation, formula of all area apparent resistivity and apparent depthparameters are developed and calculated, 2 dimensional resistivity imaging ofconcrete cutoff wall is conducted, the level of quantitative analysis of testingresults is improved.(4) Development and researching conditions of tomographic imaging,physical and mathematic foundations of concrete cutoff wall qualityinspection are summarized; Advantages & disadvantages of different raystracking technology and calculation are summarized, and straight and curvedray forward and inversion processing software of tomographic image arecompiled based on that; In accordance with the characteristics of concretecutoff wall, models with various defects are designed for forward andinversion analysis, accuracy of tomographic image used to inspect defects inconcrete cutoff wall is determined, measures to increase image resolution areforwarded; Void model is established to research the conditions of minimumresolution of tomographic image and relations between resolution capabilityand size and speed of anomalous body, the effectiveness of tomographicimaging for defect inspection of concrete cutoff wall is verified by concretemodel test; Nonlinear regression equation of wave speed and concretestrength is established based on testing data of standard modular wave speedtesting and compressive strength test, quantification level of tomographicimaging used in inspecting concrete cutoff wall is improved.更多还原