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文章以探地雷达理论为基础,结合工程实例,阐述了地质雷达在检测基坑开挖引起的地基病害中的应用。通过分析雷达测线剖面图和单道波形图,对典型的地基病害如土体疏松和脱空进行了图像解释。实践证明了地质雷达技术具有快速、准确地确定地基病害位置的能力,是地基病害快速检测的一种有效方法。 相似文献
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Ground penetrating radar (GPR) technology has been used to assess pavement performance and structure for the past 30 years in a variety of ways. Yet after all this time, the main issue remains: How well does GPR work and under what conditions? Results show that GPR works well for some situations but not as well for others. It is not currently used on a routine basis by the Departments of Transportation in the US mainly because of difficulties encountered while interpreting GPR data. These difficulties are generally attributed to the fact that the GPR reflected signals that are collected depend largely on the a priori unknown dielectric properties of the structural materials. Additional difficulties arise from the fact that physically GPR cannot detect layers unless they have sufficiently dissimilar dielectric constants. In practice, GPR has been used primarily for pavement layer thickness estimation and moisture accumulation localization within the pavement layers. To improve GPR prediction capabilities, different data processing techniques have been developed that use the GPR reflected signal to estimate the dielectric properties of surveyed structures, thus determining their thicknesses. Other signal processing techniques have also been used successfully to enhance the quality of the GPR signal in order to increase the accuracy of the data interpretation results. 相似文献
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Hideaki Miyamoto Jun'ichi Haruyama Shuichi Rokugawa Kyosuke Onishi Tetsuma Toshioka Jyun-ichi Koshinuma 《Bulletin of Engineering Geology and the Environment》2003,62(4):281-288
Ground penetrating radar (GPR) has been successfully used to detect a lava tube in a basaltic lava flow from the Fuji volcano, Japan. The target lava tube, Komoriana cave, is in the northern part of the Aokigahara lava flow which was emplaced over 1,000 years ago. The lava tube was detected by simply dragging the GPR antenna along a prefecture road, demonstrating the advantages of this method compared with detailed mapping and geological investigations. As a massive basaltic lava flow allows deep penetration of the radar pulse, the reflection radar profile obtained showed two very clear structures which were interpreted from the waveforms to be the roof and the bottom of the lava tube from the waveforms alone. This was subsequently confirmed by careful survey measurements of the Komoriana cave lava tube. The feasibility study clearly demonstrated that GPR is a very effective and convenient tool for discovering unknown lava tubes hidden deeply inside lava flows. 相似文献
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A. Giannopoulos 《Construction and Building Materials》2005,19(10):755-762
This paper deals with the fundamentals of ground penetrating radar (GPR) operation and presents a software tool that can be used to model GPR responses from arbitrarily complex targets. This software tool called GprMax is available free of charge for both academic and commercial use and has been successfully employed in situations, where a deeper understanding of the operation and detection mechanism of GPR was required. Examples from both 2D and 3D models are presented which demonstrate the use of GprMax. The tool can be downloaded from www.gprmax.orgwww.gprmax.org or by contacting the author. 相似文献
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谭伟源 《Prestress Technology》2012,16(1):21-24
介绍了TSP系统及探地雷达在隧道超前地质预报的基本原理。以TSP系统及探地雷达综合地质超前预报技术在厦深铁路某隧道的应用为例,进一步验证了该综合探测技术在隧道地质预报的准确性。 相似文献
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Marco Tallini Diego Gasbarri Danilo Ranalli Marco Scozzafava 《Bulletin of Engineering Geology and the Environment》2006,65(4):435-443
A realistic 3D view of the epikarst is key to understanding karst groundwater phenomena. Ground penetrating radar proved to
be highly effective for investigating the epikarst of a sinkhole located in the Gran Sasso karst range (central Italy). Two
different low-frequency antennae (100 MHz bistatic shielded and 40 MHz bistatic unshielded) were used. The radar signal interpretation
was correlated with field observations of the epikarst and borehole data. Two radar anomaly surfaces were identified, which
were correlated with the top and bottom of the epikarst surface. The shape of the two surfaces correlates well with the surface
topography of the study sinkhole and with the orientation of its main joints and karren. The work indicated that such a 3D
reconstruction could be usefully applied to karst aquifer vulnerability studies.
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通过植被分布规律与水资源分布的内在联系,阐明植被分布对吉林省水资源分布的影响,初步分析了植被分布在水文循环中的作用机制,从微观角度分析了植被分布与水资源分布内在联系。结果表明:吉林省水资源分布与植被分布有着密切的相关关系;植被作为水文循环的一个重要环节,是制约水资源分布规律的一个重要因素;水资源缺乏地区可大量植树造林,调节水资源的合理分布,为社会经济的发展提供必要的条件。 相似文献
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It is very important that the existing networks of underground pipelines be clearly surveyed when the underground space of an old urban area is rebuilt and expanded. The GPR method is always used to locate the embedded pipes; however, it is hard to determine their diameters, especially, when the underground pipe is full of a lossy medium (i.e., water, oil, or gas) during the operation period. First, this paper proposes a new method for probing and predicting the diameter of underground pipelines filled with lossy media based on GPR using the shape of a certain circle determined by the coordinates of three points on this circle. The operational procedure of this method is listed in detail. Secondly, this method is used to detect the diameters of underground pipelines in a model experiment and the project for the detection of a sewage pipe network in Yi’xing chemical industrial park. The measurement value is approximately consistent with the real value. Lastly, some factors influencing the accuracy of this method were comprehensively analysed by applying the finite difference time domain method (FDTD). These factors are the buried depth of the pipe, the detecting frequency of the GPR, the material of the pipe and the spacing of the measured points. The results showed that the proposed method has sufficient applicability and accuracy for practical engineering. These works demonstrate that the proposed method achieves good result. 相似文献
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探地雷达作为近10几年来新兴起来的进行地下探测和混凝土无损检测的一种高新技术,具有操作简单,结果稳定的优点。采用劳雷SIR-20型地质雷达,对某轨道梁的混凝土完整性进行检测,同时与完好梁的检测结果进行对比,该梁混凝土完整性较好。 相似文献
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探地雷达空洞探测机理研究及应用实例分析 总被引:37,自引:8,他引:29
刘传孝 《岩石力学与工程学报》2000,19(2):238-238
简要探讨了探地雷达探测空洞的机理,详细分析了两个空洞探测实例。通过理论与实践的相互结合,证实探地雷达测立洞是科学可行的,拓展了其在地球物理勘探学科中新的应用领域,表明该技术具有较强的推广潜力。 相似文献
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混凝土结构雷达检测中的钢筋相互干扰研究 总被引:4,自引:0,他引:4
探地雷达目前已被广泛地应用于土木工程领域,但其在钢筋混凝土结构中的应用并不多,主要的原因是混凝土内配筋复杂,相邻钢筋对雷达波有很大的干扰,使雷达图像难以辨识。为更好地识别复杂配筋下的雷达图像,找出其雷达图像特征,研究了各种相邻钢筋的雷达图像并得出了一些对钢筋混凝土的雷达检测有益的结论。 相似文献
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分析了探地雷达在道路无损检测中的原理,对探地雷达在路面厚度检测、路面板底脱空检测、路面密度检测、路面材料弹性模量测定及新建沥青路面的质量控制等方法的应用进行了研究,为探地雷达在道路无损检测中更好的应用和推广提供了理论与实践意义。 相似文献
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探地雷达速度参数的求取方法 总被引:1,自引:0,他引:1
探地雷达的传播速度反映介质电磁性质的变化情况,雷达记录的是来自目标体反射回波的双程走时,速度在时深转换过程中起着重要的作用,在资料处理中也经常要利用速度参数,因此速度参数的求取至关重要。文中根据已知几何尺寸的混凝土试件,结合采集的数据,详细地介绍了5种速度参数的求取方法,并指出这5种方法在实际工程中相应的适用条件。 相似文献
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断层特征参数的准确判定对地下工程的开挖与空间保持具有一定的工程地质意义。本文从实例出发 ,论证了探地雷达方法通过对断层上下盘内关键岩层位置的直接探测 ,可以间接得到断层落差。通过雷达记录剖面可以直接探测得到断层走向、倾向、倾角及位置 ,但不能查明断层面内充填物的具体情况。 相似文献
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