基于BOTDR的白泥井3号隧道拱圈变形监测   总被引：3，自引：1，他引：3  

丁勇  施斌  孙宇  赵永贵 《工程地质学报》2006,14(5):649-653

白泥井3号隧道是一条山岭隧道,隧道出口段位于滑坡等地质灾害多发的危险区域,为了确保隧道安全,应用国际上先进的BOTDR分布式应变测量技术,对隧道拱圈截面变形进行了分布式应变监测。本文着重介绍了BOTDR在隧道内安装布设以及监测数据的分析过程,监测成果显示,在将近1 a的监测时间里,隧道拱圈基本保持稳定,只是在个别区域,如K84+508.2处拱圈截面的衬砌表面发生张拉变形,变形量在雨季期间达到最大,据分析是由于雨水入渗山体造成围岩压力增大,致使拱圈截面受挤压变形。  相似文献   

我国隧道地质超前预报技术述评   总被引：19，自引：4，他引：19       下载免费PDF全文

宋先海  顾汉明  肖柏勋 《地球物理学进展》2006,21(2):605-613

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   

Monitoring urban growth on the European side of the Istanbul metropolitan area: A case study     

S. Kaya  P.J. Curran 《International Journal of Applied Earth Observation and Geoinformation》2006

Istanbul is the largest city in Turkey with an area of around 5750 km² and a population of around 10.8 M (2000). In 1980, the population was only around 4.7 M and so has more than doubled in only 2 decades. In 2000, around 65% of the population were living on the European side of the city with its large industrial/commercial and trade centres. The population is increasing as a result of both births exceeding deaths and mass immigration. Consequently, planned and unplanned housing are increasing while green areas are decreasing in area. Monitoring urban growth will enable the Municipality of Istanbul to better manage this complex urban area.  相似文献   

Bioaccumulation of radiocaesium in Arctic seals     

Carroll J  Wolkers H  Andersen M  Rissanen K 《Marine pollution bulletin》2002,44(12):1366-1371

Seals are high trophic level feeders that bioaccumulate many contaminants to a greater degree than most lower trophic level organisms. Their trophic status in the marine food web and wide-spread distribution make seals useful sentinels of arctic environmental change. The purpose of this investigation is to document the levels and bioaccumulation potential of radiocaesium in high latitude seal species for which data have not previously been available. The study was carried out on harp, ringed, and bearded seals caught north of the island archipelago of Svalbard (82°N) in 1999. The results are then compared with previous studies in order to elucidate factors responsible for bioaccumulation in Arctic seals. Concentrations of ¹³⁷Cs were determined in muscle, liver and kidney samples from a total of 10 juvenile and one adult seal. The mean concentration in muscle samples for all animals was 0.23±0.045 Bq/kg f.w. ¹³⁷Cs concentrations in both liver and kidney samples were near detection limits (≈0.2 Bq/kg f.w.). The results are consistent with previous studies indicating low levels of radiocaesium in Arctic seals in response to a long term trend of decreasing levels of ¹³⁷Cs in the Barents Sea region. Bioconcentration factors (BCFs) estimated for seals from NE Svalbard are low, ranging from 34 to 130. Comparing these values with reported BCFs for Greenland seals from other sectors of the European Arctic, we suggest that the combination of physiological and ecological factors on radiocaesium bioaccumulation is comparable among different Arctic seal populations. The application of this work to Arctic monitoring and assessment programs is discussed.  相似文献   

填土地基强夯试验监测研究     

叶建辉  黄蓬源 《福建地震》1998,(4)

本文简要介绍福建漳州某地填土地基强夯试验监测项目,利用钻探、原位测试及孔隙水压力、水平位移、螺旋沉降、磁性分层沉降、水位及沉降标观测等试验监测手段,对强夯加固填土地基试验进行监测研究,并对强夯效果作出评价。  相似文献   

重力方法在地震预报中的作用   总被引：1，自引：0，他引：1  

吴雪芳 《地震》1996,16(1):90-95

利用重力方法研究地球的潮汐和非潮汐变化。通过它们的变化规律了解地下介质的质量变化和密度分布以及地球弹性模量与地震的关系。２０多年地震预报实践表明，重力方法在地震预报中有其特殊作用。根据目前在台站或测点按波速异常所圈定的孕震区内发生的地震统计检验：台站监测能力为４４％，重力重复测量的监测能力可达５６％。  相似文献   

Analysis of microtremors within the Provadia region near a salt leaching mine     

P. Knoll  G. Kowalle  K. Rother  B. Schreiber  I. Paskaleva 《Pure and Applied Geophysics》1996,147(2):389-407

By analysis of microtremors recorded with digital seismological monitoring equipment near the Provadia salt diapir (Bulgaria), two groups of events showing different characteristics have been detected in the vicinity of the salt production area. The first group of events has low magnitudes and is located at a distance of about 1 km from the top of the salt diapir. These events show low stress drops. The second group of tremors is located outside the salt diapir. The corresponding magnitudes and stress drops are larger. The first class of events seems to be related to processes at the contour of the salt leaching caverns, whereas the origin of the second group seems to be connected with stress redistribution processes around the salt body. Based on this analysis, the tectonic model of the Provadia salt diapir has been modified.  相似文献   

监测网参数的可估性     

周世健  吴子安 《测绘工程》1996,5(1):8-13

监测网是一类特殊的控制网。本文根据可估定义，讨论了监测网中一些参数的可估问题，得到位移向量为不可估量，变形参数为可估量，此结论对于监测网的数据处理和设计具有较大的指导作用。  相似文献   

地磁观测仪器状态监视报警系统的研制     

李铁  史宏伟 《东北地震研究》2003,19(4):61-66

使用简单的编码电路实现了地磁仪器观测工作状态的远程监视，有助于减少停记，提高观测质量。与防盗监视报警结合更提高了其应用价值。  相似文献   

忻州市重点水源地监测调查报告     

崔丙玉  孙和平 《地下水》2003,25(3):138-140

忻州市重点水源地的建设，关系到两地城市工、农业生产用水及生活用水等。为确保水资源的可持续利用，保证国民经济可持续发展，开展重点水源地调查和研究已成为一项十分必要和紧迫的工作。本调查报告为科学化管理水资源提供了第一手资料。  相似文献