探地雷达地下界面成像   总被引：3，自引：1，他引：3  

肖兵  宋守根  何继善 《物探与化探》1996,20(4):304-308

由Maxwell方程,根据雷达波在介质中的高频传播特性,导出雷达波满足的波动方程。由此求出波速扰动量的成像公式,利用小波变换分析下界面的奇异性,从而达到雷达信号地下界面成像的目的。  相似文献   

探地雷达技术及其应用和发展   总被引：13，自引：2，他引：13  

肖兵  周翔  汤井田 《物探与化探》1996,20(5):378-383

作者对近年来探地雷达的技术发展及新的应用研究进行了概括和总结。在详细分析探地雷达方法原理、系统结构的基础上,提出了改进探地雷达系统结构的思路;同时,针对探地雷达工作中的高噪声和地震数据处理技术移植的不适应性,提出了探地雷达地下界面高分辨率成像的新方法。  相似文献   

地质雷达及其在环境地质中的应用   总被引：24，自引：2，他引：24  

杜树春 《物探与化探》1996,20(5):384-392

本文结合近几年联邦德国在环境地质方面的研究工作对地质雷达在环境工程领域中的应用范围及其局限性作了简要总结,文中并介绍了地质雷达技术的方法原理及存在问题。  相似文献   

RAMAC/GPR探地雷达在机场滑行道探测中的应用     

南生辉 《煤田地质与勘探》1997,(Z1)

采用RAMAC／GPR探地雷达对机场跑道传力杆进行探测试验，取得了令人满意的效果，为机场工程质量检测提供了一种有效手段。  相似文献   

巷道围岩松动圈的地质雷达探测及应用   总被引：9，自引：1，他引：9  

杨永杰  毛仲玉 《工程地质学报》1997,5(3):276-281

在简述地质雷达探测原理的基础上, 分析了巷道围岩松动圈雷达探测的可行性。结合华丰矿巷道围岩松动圈探测实例, 提出了松动圈雷达探测方法、图像分析及探测结果应用。结果表明, 采用地质雷达探测巷道围岩松动圈是可行的, 可以用于指导巷道围岩的锚杆支护设计。  相似文献   

Observational and Numerical Study on the Influence of Large-Scale Flow Direction and Coastline Shape on Sea-Breeze Evolution     

Robert C. Gilliam  Sethu Raman  Dev Dutta S. Niyogi 《Boundary-Layer Meteorology》2004,111(2):275-300

In this study radar, surface observations and numericalsimulations are used to examine the inland penetrationand intensity of the sea breeze during various large-scaleflow regimes along the curved coastline of the Carolinas,U.S.A. The results clearly indicate that the flow directionrelative to the curved coastline has a significant effecton the sea-breeze evolution.Overall, during northerly flow regimes alongthe curved North Carolina coast, observationsand numerical simulations show that the sea-breezefront has a tendency to remain close to the south-facingcoast. During these same flow regimes the frontmoves further inland relative to the east-facingcoast. The sea-breeze front during westerly flowcases progressed further inland relative to the southcoast and less so from the east-facing coastline.South-westerly flow allows the sea breeze to moveinland from both coastlines but the coastal shapeinfluence makes the inland penetration less fromthe easterly facing beaches. During periods of lightonshore flow (south-east), the sea breeze movesconsiderable distances inland but is not discernableuntil later in the afternoon. The simulations indicatedthat the sea-breeze intensity is greatest (least) when thelarge-scale flow direction has an offshore (onshore)component. Model results indicate the existence of astrong front well inland in the late afternoon duringlight onshore flow. Also noted was that the simulatedsea-breeze front develops earlier in the afternoon duringoffshore regimes and later in the day as the large-scaleflow becomes more onshore. It is concluded that thecoastline shape and coast-relative flow direction areimportant factors in determining how the sea-breezecirculation evolves spatially.  相似文献   

天山乌鲁木齐河源一号冰川探地雷达测厚及其数据分析     

何茂兵 孙波杨亚新  焦克勤 《华东地质学院学报》2004,27(3):235-239

探地雷达是一种利用电磁波的反射原理探测地下介质分布特征的地球物理勘探技术，在冰川研究中发挥了重要作用。在天山一号冰川上用探地雷达进行了探测，获得了能够清晰地分辨冰一岩界面的雷达剖面。根据这些雷达剖面读出冰厚值，再结合最新的冰川地形图，作出了天山一号冰川的冰厚等值线图和冰下地形图；并由天山一号冰川最新的表面积数据推算了冰储量。  相似文献   

地质雷达在隧道检测中的应用   总被引：3，自引：0，他引：3  

韩自豪牛向东  周建雄万广达 彭南宁 《中国煤田地质》2004,16(2):47-48,56

隧道施工完成后用常规方法很难对衬砌质量做出系统评价，地质雷达利用超高频脉冲电磁波探测目标介质的介电常数，很容易掌握砼衬砌结构的厚度、衬砌周围回填及空隙情况，围岩断层裂隙构造情况等，为工程技术评价提供依据。文章以实例，介绍了利用地质雷达对隧道进行检测所使用的仪器、工作参数及地质雷达资料处理解释步骤，并通过对几幅典型雷达图像进行分析介绍了不同异常结构在雷达剖面上的反映。  相似文献   

A new method of testing pile using dynamic P-S-curve made by amplitude of wave train     

Hu Yi-li  Xu Jun  Duan Yong-kong  Xu Zhao-yong  Yang Run-hai  Zhao Jin-ming 《地震学报(英文版)》2004,17(6):725-734

A new method of detecting the vertical bearing capacity for single-pile with high strain is discussed in this paper. A heavy hammer or a small type of rocket is used to strike the pile top and the detectors are used to record vibration graphs. An expression of higher degree of strain (deformation force) is introduced. It is testified theoretically that the displacement, velocity and acceleration cannot be obtained by simple integral acceleration and differential velocity when long displacement and high strain exist, namely when the pile phase generates a whole slip relative to the soil body. That is to say that there are non-linear relations between them. It is educed accordingly that the force P and displacement S are calculated from the amplitude of wave train and (dynamic) P-S curve is drew so as to determine the yield points. Further, a method of determining the vertical bearing capacity for single-pile is discussed. A static load test is utilized to check the result of dynamic test and determine the correlative constants of dynamic-static P(Q)-S curve. Foundation item: Key projects of the tenth Five-year Plan of Yunnan Province (documented Yunnan district [2002]54-02-02) and Geophysical Society of Yunnan Province.  相似文献   

Hydrological connectivity of soil pipes determined by ground‐penetrating radar tracer detection     

Joseph Holden 《地球表面变化过程与地形》2004,29(4):437-442

Soil pipes are common and important features of many catchments, particularly in semi‐arid and humid areas, and can contribute a large proportion of runoff to river systems. They may also signi?cantly in?uence catchment sediment and solute yield. However, there are often problems in ?nding and de?ning soil pipe networks which are located deep below the surface. Ground‐penetrating radar (GPR) has been used for non‐destructive identi?cation and mapping of soil pipes in blanket peat catchments. While GPR can identify subsurface cavities, it cannot alone determine hydrological connectivity between one cavity and another. This paper presents results from an experiment to test the ability of GPR to establish hydrological connectivity between pipes through use of a tracer solution. Sodium chloride was injected into pipe cavities previously detected by the radar. The GPR was placed downslope of the injection points and positioned on the ground directly above detected soil pipes. The resultant radargrams showed signi?cant changes in re?ectance from some cavities and no change from others. Pipe waters were sampled in order to check the radar results. Changes in electrical conductivity of the pipe water could be detected by the GPR, without data post‐processing, when background levels were increased by more than approximately twofold. It was thus possible to rapidly determine hydrological connectivity of soil pipes within dense pipe networks across hillslopes without ground disturbance. It was also possible to remotely measure travel times through pipe systems; the passing of the salt wave below the GPR produced an easily detectable signal on the radargram which required no post‐processing. The technique should allow remote sensing of water sources and sinks for soil pipes below the surface. The improved understanding of ?owpath connectivity will be important for understanding water delivery, solutional and particulate denudation, and hydrological and geomorphological model development. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献