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2004年对南水北调引水隧洞西线一期工程中玛柯河－贾曲段20 km深埋长隧洞进行了地质结构面、岩性特征、赋水性等地球物理勘探、工程地质勘查,并进行综合解释以查清勘探区影响引水隧洞工程建设的不良地质体和不良地质构造.本文介绍了CSAMT法隧洞勘探的特点、资料采集的过程及应特别注意的复杂地形资料处理技术,结合其他补充物探手段及地面工程地质勘察结果对20 km深埋长隧洞围岩介质的结构特征进行了解释,指出了可能影响工程的断层、破碎带及异常区 相似文献
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Automatic extraction of geometrical characteristics hidden in ground‐penetrating radar sectional images using simultaneous perturbation artificial bee colony algorithm 
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下载免费PDF全文 Ground‐penetrating radar is one of the most effective methods of detecting shallow buried objects. Ground‐penetrating radar radargram is a vertical map of the radar pulse reflections that returns from subsurface objects, and in the case of cylindrical objects, it would be a hyperbola. In order to get clear and accurate information on the presence, location, and geometry of the buried objects, the radargrams need to be interpreted. Interpretation of the results is a time‐consuming task and needs an expert with vast knowledge. Development of an automatic interpretation method of B‐scan ground‐penetrating radar images would be an effective and efficient solution to this problem. A novel automatic interpretation method of ground‐penetrating radar images, based on simultaneous perturbation artificial bee colony algorithm using tournament selection strategy, simultaneous perturbation stochastic approximation method, and new search equations, is introduced in this paper. The proposed algorithm is used to extract geometrical parameters, i.e. depth, location, and radius, of buried cylindrical objects in order to assess its accuracy. Synthetic data, simulated using GprMax2D forward modelling program, and real data, surveyed in the campus of Isfahan University of Technology, are used in the assessment. The performance of the proposed method in detecting synthetic hyperbolas is compared with that of the original artificial bee colony algorithm, genetic algorithm, and modified Hough transform. The results show superiority of the proposed algorithm, in detecting synthetic hyperbolas. Furthermore, the performance of the proposed method in estimating depth and radius of pipes in real ground‐penetrating radar images is compared with that of the modified Hough transform. The results indicate higher accuracy of the proposed method in estimating geometrical parameters of the buried cylindrical objects. 相似文献
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国内外的隧道地质超前预报技术正在发展之中,目前应用的负视速度法,水平剖面法,TSP、TGP等技术,由于观测方式和资料处理方法比较简单,不能准确确定掌子面前方围岩的波速,从而致使地质界面定位不准确,围岩工程类别划分缺乏依据,亟待改进.TRT与TST技术采用空间观测方式和偏移成像方法,技术比较先进,能解决了掌子面前方围岩速度结构可靠分析的问题,实现了隧道围岩地质结构的精确成像,适合复杂地质条件下的地质超前预报应用.目前的超前预报过于依赖地震方法,实际上地震方法对于解决构造问题比较有效,解决含水性问题不如电磁方法,高密度电法和瞬变电磁方法在超前预报领域会有广阔的应用前景.实际预报工作中要取得好的预报结果,必须提倡综合方法,提倡地质分析与工程物探相结合,地震方法与地磁方法相结合,共同解决不良地质构造、含水构造、含瓦斯气构造的超前预报问题. 相似文献
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综合地质预报技术在岩溶区隧道施工中的应用 总被引：1，自引：0，他引：1
通过对地质分析法、地质雷达、红外探测,超前水平钻孔等超前地质预报技术在某隧道中岩溶预报中的应用研究,对比分析几种地质预报技术的特点,得到由多种预报手段综合而成的预报系统的实用性以及在指导施工方面的作用优于单一地质预报方法的结论,并对照实际开挖情况提出针对岩溶地质条件的施工建议. 相似文献
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隧道地质超前预报在隧道施工开挖中起着关键性作用,同时也是工程地球物理界所面临的一大技术难题.本文回顾了我国主要隧道地质超前预报技术（隧道地震预报系统、水平声波剖面法、陆地声纳法、地质雷达法、红外探水法、超前钻探法和超前平导法）的历史,介绍了它们近年来的研究进展;分析了其现状及在几何结构成像、物性结构反演成像和复杂地质体结构探测中存在的不足;指出了当前亟待解决的基础理论研究、正反演研究、多参数综合利用、建立三维可视化的预测预警系统等问题并提出了解决这些问题的基本设想. 相似文献
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道路塌陷空洞一直是威胁交通安全运行的重要隐患,对道路塌陷空洞的探测方法进行研究具有重大的现实意义。研究工作通过实例探讨三维探地雷达（GPR）对道路塌陷区进行探测的方法技术及其应用效果。为查明道路塌陷空洞的空间分布特征,在塌陷区布设了共23条测线,1.0 m×0.5 m的三维测网并进行数据采集;通过对雷达数据进行处理,获得不同测线、不同方向的三维雷达剖面。结合地质情况对上述图件进行综合分析与解释,准确地查明塌陷空洞的位置、埋深及发育程度;经开挖验证,解译结果可靠。工程实践表明,三维探地雷达技术可以快速、高效地应用于道路塌陷探测中,其探测结果可为塌陷区后续施工以及安全防治提供参考。 相似文献
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隧道施工过程中,经常遇到突水、突泥和坍塌等无法预料的地质灾害,给施工安全带来了重大灾难和无法估计的经济损失,为了保证隧道施工安全,对不良地质体的发育情况进行准确及时的超前预报,是当前隧道设计与施工中亟待研究与解决的关键问题.详细介绍了TSP-203超前预测预报原理及方法,针对渝宜高速公路某隧道复杂的地质条件,在施工过程中进行了超前地质预测预报,并对预报结果进行了较为详细的处理和分析,同时根据隧道施工现场高压区富水层等地质情况,对隧道外水荷载计算方法和衬砌设计结构进行了分析.结果表明,预报成果与实际情况基本吻合,有效地指导了隧道施工. 相似文献
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An increase of the spatial and temporal resolution of snowpack measurements in Alpine or Arctic regions will improve the predictability of flood and avalanche hazards and increase the spatial validity of snowpack simulation models. In the winter season 2009, we installed a ground‐penetrating radar (GPR) system beneath the snowpack to measure snowpack conditions above the antennas. In comparison with modulated frequency systems, GPR systems consist of a much simpler technology, are commercially available and therefore are cheaper. The radar observed the temporal alternation of the snow height over more than 2·5 months. The presented data showed that with moved antennas, it is possible to record the snow height with an uncertainty of less than 8% in comparison with the probed snow depth. Three persistent melt crusts, which formed at the snow surface and were buried by further new snow events, were used as reflecting tracers to follow the snow cover evolution and to determine the strain rates of underlaying layers between adjacent measurements. The height in two‐way travel time of each layer changed over time, which is a cumulative effect of settlement and variation of wave speed in response to densification and liquid water content. The infiltration of liquid water with depth during melt processes was clearly observed during one event. All recorded reflections appeared in concordance with the physical principles (e.g. in phase structure), and one can assume that distinct density steps above a certain threshold result in reflections in the radargram. The accuracy of the used impulse radar system in determining the snow water equivalent is in good agreement with previous studies, which used continuous wave radar systems. The results of this pilot study encourage further investigations with radar measurements using the described test arrangement on a daily basis for continuous destruction‐free monitoring of the snow cover. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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地质雷达能快速、准确地探测地下潜在的地质缺陷体的空间位置、形状大小及电性质等其他一些地质参数,可以为滑坡的加固设计、施工提供可靠的资料,简述了地质雷达的勘探原理和方法,并以实例说明了地质雷达在滑坡治理中的应用方法及效果。 相似文献
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Paulo Roberto Antunes Aranha Cristina Helena Ribeiro Rocha Augustin Frederico Garcia Sobreira 《Journal of Applied Geophysics》2002,49(4)
Ground penetrating radar (GPR) has been used as a tool to access information about ground subsurface features. Such information is very important for different types of studies, varying from those related to archeological research to those studying geological elements of bedrock. More recently, however, GPR has been increasingly applied to environmental studies, especially for soil research. This paper presents the results of an application of GPR for the study of weathered profiles. GPR was used to discover the degree of trustworthiness of the information on the ground subsurface through the interpretation of the results of the radar sections as well as the data collected from boreholes, which reached until 21 m. The results show a relatively high degree of details obtained by GPR, indicating the possibility of speeding up ground subsurface surveys related to geomorphological, geological, and pedological studies. 相似文献
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以页岩的不良工程性质和围岩分级依据为基础,探讨公路隧道页岩浅埋段的超前地质预报方法的优化组合.通过比较国内外现有的各种超前地质预报方法的优缺点,提出了以TSP法和双频激电法为主、根据工程项目的等级适当考虑采用探地雷达作为补充的一套组合方案.而在某些特别复杂地段建议采用水平钻探加以验证.应用这套方案在常（德）—张（家界）高速公路第十合同段的关口垭隧道进行了一次科研试验,对预报结果进行详细的处理和分析后,给施工单位提出了相应的施工建议.后期的跟踪调查结果表明,试验成果与实际情况基本吻合,给予了施工正确的指导,达到了试验目的. 相似文献
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在玉昆铁路柿花树隧道不良地质发育的洞段进行红外探水工作期间,常用的分析方法有时无法预判掌子面前方是否存在隐伏水体或含水构造。为了提高红外探水短距离预报的准确率,用模糊聚类法将掌子面测点场强的数据分类,根据开挖传递的地质信息,研究模糊聚类结果的变化规律、突水风险与岩体破碎程度之间的关系。实践证明,模糊聚类法和常用分析方法的结合,使红外探水取得了较好的预判效果。 相似文献
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Groundwater inflow estimation is essential for the design and construction of tunnel and the assessment of the environmental impacts. Analytical solutions used in current engineering practice do not adequately account for the effect of the excavation‐induced drawdown, which leads to significant change in pore water pressure distribution and reductions of the water level beyond tunnel. Based on the numerical analysis results, this article proposes semianalytical method to predict the height of lowered water level and groundwater tunnel inflow. The tunnel problem is conceptualized as two‐dimensional flow in a plane perpendicular to the tunnel axis. The analytical formula, considering the effect of the excavation‐induced drawdown, provides a better prediction of the tunnel inflow compared to the existing analytical formulas, even for the cases with inclined groundwater level. 相似文献
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Measuring snow ablation rates in alpine terrain with a mobile multioffset ground‐penetrating radar system 下载免费PDF全文
下载免费PDF全文 Ground‐penetrating radar (GPR) has become a promising technique in the field of snow hydrological research. It is commonly used to measure snow depth, density, and water equivalent over large distances or along gridded snow courses. Having built and tested a mobile lightweight set‐up, we demonstrate that GPR is capable of accurately measuring snow ablation rates in complex alpine terrain. Our set‐up was optimized for efficient measurements and consisted of a multioffset radar with four pairs of antennas mounted to a plastic sled, which was small enough to permit safe and convenient operations. Repeated measurements at intervals of 2 to 7 days were taken during the 2014/2015 winter season along 10 profiles of 50 to 200 m length within two valleys located in the eastern Swiss Alps. Resulting GPR‐based data of snow depth, density, and water equivalent, as well as their respective change over time, were in good agreement with concurrent manual measurements, in particular if accurate alignment between repeated overpasses could be achieved. Corresponding root‐mean‐square error (RMSE) values amounted to 4.2 cm for snow depth, 17 mm for snow water equivalent, and 22 kg/m3 for snow density, with similar RMSE values for corresponding differential data. With this performance, the presented radar set‐up has the potential to provide exciting new and extensive datasets to validate snowmelt models or to complement lidar‐based snow surveys. 相似文献
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F. K. BOULOS 《Geophysical Prospecting》1972,20(2):304-316
Electrical resistivity sounding was attempted with success in 1960 on the surface of the Nile water in Khor Kundi El-Bahari, the starting place for the construction of the offset channel of the High Dam. The method was applied to determine the depth to the upper surface of the granite below the alluvium and Nile water. The success of the method conducted at two stations in the Khor is attributed to the favourable geological conditions of the section which consists of nearly homogeneous layers besides the good earthing conditions of electrodes dipped in water. The high resistivity contrast between water and granite facilitates interpretation of sounding curves. Factors interfering with the results of interpretation are mentioned. 相似文献
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