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1.
The year was particularly eventful in terms of the recognition of improved technologies impinging on the duties of the Engineering Geologist. National economies were strained to the limit under the pressure of the new world terrorist attacks and burgeoning populations. much of which stemmed from escapes from oppressive national regimes to the free world. The impacts of terrorism range from increased danger and costs of field work, to special design considerations and postponed and delayed project work.On the positive side, continued progress has been made in the means of recognition and professional development of our practitioners and in the general call for their work. Competent engineering geologists are in consistent demand, but the working conditions are not improved. A general deterioration of university funding, aggravated by bureaucratic excesses among administrators, have tended to make life miserable for dedicated faculty and a general move is afoot to cut back on the number of funded geology departments in North America and Europe. This situation has also been worsened by the general withdrawal of the mineral industries and by retraction of the petroleum companies from all but their most favored campuses.  相似文献   

2.
赵勇刚  刘江 《物探与化探》2007,31(Z1):116-118
随着国民经济的不断发展,各种工程建设不断增多,各种滑坡、边坡及其工程产生的滑坡、边坡灾害越来越多。由于许多滑坡、边坡是在工程进行中产生的,由于时间紧,要求选择一个方便、高效、快捷的勘察方法。笔者结合工程实例介绍了瞬态面波剖面法作为一个快捷、高效的勘察方法在滑坡勘察中应用及其效果。  相似文献   

3.

The interpretation of aquifer responses to pumping tests is an important tool for assessing aquifer geometry and properties, which are critical in the assessment of water resources or in environmental remediation. However, the responses of aquifers, measured by time-drawdown relationships in monitoring wells, are nonunique solutions that are affected by many factors. Jacob’s Zoo is a collection of graphical interpretations that allows students and practitioners to develop an intuitive feel for how natural hydrogeological systems work, and develop a set of skills that provide a better understanding of aquifer properties far beyond interpretation of pumping tests. Jacob’s Zoo, based on the work of Jacob (1950), fosters a deeper understanding, although few practitioners realize the full utility of the method. Jacob CE (1950) Flow of groundwater, In: Rouse H (ed) Engineering Hydraulics, Wiley, New York. P 321–386.

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4.
程国栋  马巍 《冰川冻土》2003,25(3):303-308
2002年9月2~4日在俄罗斯雅库茨克市召开了第五届冻土工程国际学术讨论会,会议针对4个专题进行了讨论:土的物理和力学、多年冻土区工程建筑物的建筑和应用问题、开发有用矿床中的冻土问题和道路建筑.通过此文将国际上的一些最新研究动态给予介绍,给从事寒区工程研究的工作者以借鉴.  相似文献   

5.
Over the past two decades development has been shifting its focus toward smaller scales and particular problems. As a result, the household has become an increasingly important institution for development, and has come under increased scrunity as development practitioners and scholars seek to better understand this institution’s functions and foundations, trying to ‘get the household right’. These efforts, rather than clarifying the character and the function of the household, have contributed to its indeterminacy by reifying the very institution they seek to analyse. Arguing that these efforts fundamentally miss the point of examining the household, this paper introduces a different framework of analysis that addresses the household not as a fixed object of research, but as a local construction that embodies flows of power and knowledge both within and transcending the local. Using the example of varying constructions of the household in two villages in Ghana’s Central Region, this article illustrates how such an approach allows us to address the various functions of the household as particular embodiments of these flows, an approach that better explains the endurance or ephemerality of these functions. Such an approach provides a stronger foundation for the consideration of how particular constructions of this institution may have troubling implications for issues like gender equity and sustainability.  相似文献   

6.
A Methodology for Reliability-Based Design of Rock Slopes   总被引:10,自引:0,他引:10  
Summary A reliability-based methodology for the design of rock slopes, that can easily be implemented by the practicing engineers is proposed. The advanced first-order second-moment (AFOSM) method is adopted as the reliability assessment model and its application is illustrated for the case of plane failure. A model is developed within the framework of first-order second-moment approach to analyze the uncertainties underlying the in situ shear strength properties of rock discontinuities. Here, particular emphasis is given on the assessment of uncertainties related to the shear characteristics of clean, unfilled rock discontinuities under low normal stress levels. An extensive literature survey on the shear characteristics of discontinuities is carried out in order to collect data for the quantification of uncertainties. The data extracted from this literature survey are classified and reprocessed so that they can be utilized in the uncertainty analysis model. A user friendly software called ROCKREL is developed to carry out the numerical computations and to make the proposed design format more practical. Received April 16, 2001; accepted June 10, 2002; Published online November 19, 2002 Authors' address: Prof. Celal Karpuz, Middle East Technical University, Faculty of Engineering, Department of Mining Engineering, 06531 Ankara, Turkey; e-mail: karpuz @metu.edu.tr  相似文献   

7.
冻土工程国家重点实验室的回顾与展望   总被引:7,自引:2,他引:5  
马巍  朱元林 《冰川冻土》1998,20(3):264-272
冻土工程国家重点实验室是我国唯一的一个以冻土工程为主要研究内容的综合性实验室,其建设和发展对促进我国冻土学的发展有非常重要的意义,在迎来兰州冰川冻土研究所建所40周年之际,冻土工程国家重点实验室也走过了近9年的历程,回顾昨天,展望未来,只有紧紧把握粘土学科前沿,创新超前,解决国家在寒区经济和社会发展中提出的基础性,关键性和综合性的工程和资源环境问题,才能创建一流的国家重点实验室,使我国冻土工程研究  相似文献   

8.
现行的勘察设计行业《岩土工程勘察规范》(GB50021-2001/2009年版)、《建筑抗震设计规范》(GB50011-2010)、《工程场地地震安全性评价》(GB17741-2005),对于活动断裂的定义有一定差异,使得不同的勘察设计单位对同一条断裂的评价结果不一致,甚至相互矛盾。本文以昆明市为例,通过分析不同规范对于活动断裂的定义,指出其中的问题与差异,结合典型断层地质剖面与震害实例,简要阐述地质上判定活动断裂的主要依据,即不应以《岩土工程勘察规范》(GB50021-2001/2009年版)规定的全新地质时期(一万年)内有无地震活动来判定断裂是否为全新活动断裂,应以《工程场地地震安全性评价》(GB17741-2005)规定的断裂是否错动地表或近地表相应时代的地层,来判定其活动时代。  相似文献   

9.
Geotechnical and Geological Engineering - Urbanization and development in arid and semiarid have brought increased interest in the improvement of water sensitive soils susceptible to volume change....  相似文献   

10.
朱元甡 《水文》2006,26(6):1-5,67
考虑到我国水资源短缺、水灾害频发和水环境恶化的情势,在水利建设和管理中,突出风险意识是非常必要的和十分及时的。我们多年从事风险分析实践的感悟是:水利风险模拟分析完全不同于建筑结构物的可靠度计算,更不是模拟设计洪水的淹没范围和水深,其真谛是在于如实模拟出当地的水旱灾害的不确定性,是对传统思维模式的重大的突破。有些传统理念也有必要作调整,如:工程水文学科的内涵,可持续发展的不确定性和风险分析的风险。  相似文献   

11.
Summary This paper investigates whether a micromechanical model developed to investigate the relation between the basic failure processes at grain-scale and the macroscopic failure pattern can be applied to model the fracturing around large-scale excavations. The simulated fracture pattern around a vertical shaft is compared to the fracturing around a shaft at a depth of 3400 m. The simulations suggest that wedge-shaped zones, called dog-ears, are formed by a progressive splitting-like failure of the rock. The fractures forming these slabs nucleate in the zones subjected to the highest compressive stresses. Both shear and tensile mechanisms are responsible for the fracturing. The dog-ears deepen and widen as spalling continues. Received June 5, 2001; accepted September 24, 2002; Published online January 21, 2003 Acknowledgements The simulations presented in this paper form part of the PhD study of B. Van de Steen at the KULeuven. The authors wish to thank the sponsors of the Deepmine project for the permission to use the information pertaining to the fracturing around the South shaft at Western Deep Levels. Authors' address: André Vervoort, Katholieke Universiteit Leuven, Faculty of Engineering, Department of Civil Engineering, Kasteelpark Arenberg 40, B-3001 Leuven, Belgium; e-mail: andre.vervoort@bwk.kuleuven.ac.be  相似文献   

12.
The Effect of Normal Stiffness on the Shear Resistance of RockThis paper presents the theory and design of a shear machine whose normal stiffness could be varied by four orders of magnitude. Experimental techniques, testing procedures, and special equipment designed by the Bureau of Mines for determining the effect of normal stiffness on the shear stress-normal displacement behavior of intact and prepared joint surfaces of both hard (granite) and soft (sandstone) rock under constant shear displacement rate are described. Experimental results are presented which show that the effect of increasing the normal stiffness on either intact rock or fractured surfaces is to provide increased normal confinement. Increased normal confinement results in an increased shear strength for rock. Engineering significance of this result is discussed.  相似文献   

13.
Over the past two decades development has been shifting its focus toward smaller scales and particular problems. As a result, the household has become an increasingly important institution for development, and has come under increased scrunity as development practitioners and scholars seek to better understand this institution’s functions and foundations, trying to ‘get the household right’. These efforts, rather than clarifying the character and the function of the household, have contributed to its indeterminacy by reifying the very institution they seek to analyse. Arguing that these efforts fundamentally miss the point of examining the household, this paper introduces a different framework of analysis that addresses the household not as a fixed object of research, but as a local construction that embodies flows of power and knowledge both within and transcending the local. Using the example of varying constructions of the household in two villages in Ghana’s Central Region, this article illustrates how such an approach allows us to address the various functions of the household as particular embodiments of these flows, an approach that better explains the endurance or ephemerality of these functions. Such an approach provides a stronger foundation for the consideration of how particular constructions of this institution may have troubling implications for issues like gender equity and sustainability.  相似文献   

14.
本文首次报道福建境域湖泊沉积物中有毒元素含量的变化。根据对晋江市龙湖 4 0多年来沉积柱的环境地质演化的研究 ,发现其污染度自 1976~ 2 0 0 2年呈急速上升态势。其中上升最快的元素为 Cd、Hg、As、Pb、Cu、Zn、Cr,尤以 Cu最为典型 ,其污染度变化可分为三个时段 :11976~ 1984年污染指数 0 .6 7,为微污染 ;21984~ 1993年污染指数 0 .86 ,为轻污染 ;31993~ 2 0 0 2年污染指数 2 .37,为重污染。第二时段的污染度为第一时段的 1.3倍 ,第三时段的污染度为第一时段的 3.5倍。表明污染度增加是十分迅速和严峻的。值得引起我们高度关注的是 ,1984~ 2 0 0 2年 ,19年间龙湖中剧毒元素 Hg、As、Pb的平均含量均超越国家标准 ,为污染环境。 2 0 0 2年 4月龙湖表面沉积中这 3种剧毒元素分别为 1976~ 1984年时段含量最低值的 4 6 .3倍、3.3倍、1.9倍 ,已大大超过其“警戒线”(如 Hg为标准值的 4 .4倍 ) ,显示龙湖污染的严重性。龙湖环境地质条件的日益恶化 ,对人群健康已造成一定影响 (如癌症病人日益增加 ) ,这也警示着日本水俣病可能在该地区重演  相似文献   

15.
实践证明,常规固定试验(压缩试验)可以采用快速法替代现行规范的慢速法。本文在大量统计对比和相应理论分析基础上提出上海地区经验修正系数K值,以利快速法的推行。  相似文献   

16.
李艺  周红军 《探矿工程》2017,44(11):1-7
《探矿工程》杂志创刊于1957年10月。60年来,曾两度停刊、复刊,几次变更刊名,几易主办单位,在历届编委会和编辑部的努力和坚守下,在广大读者、作者的支持和陪伴下,顽强地走过了风雨兼程的60年。她在书写自己60年辉煌历史的同时,也完成了一部记录中国探矿工程技术发展历史的巨著。当前她正面临着来自学科调整、评价体系、新兴媒体等的冲击以及经济方面的压力。展望未来,将继续坚持注重实用性、理论与实践相结合、学习国外先进经验的办刊宗旨,继续做探矿工程(岩土钻掘工程)技术发展的忠实记录者。  相似文献   

17.
长白山天池火山自1985年起每年6~9月开展季节性地震观测。1985~1994年平均每年记录到的火山地震在40次以内。从2002年7月开始,长白山天池火山地震数量明显增加,2003年发生1293次地震,2004年虽然地震数量略有下降,但是能量释放持续增强。近年来,长白山周边地区地震活动明显增强,2004年12月和2005年4月在距离长白山天池30多公里的抚松县发生了4.4级和4.0级构造地震。长白山附近发生了多次地震和火山震,天池口附近有强烈震感,可听到地声,并造成轻微震害。2005年8月以后火山地震渐趋平静,逐渐恢复到2002年以前的地震活动水平。本文对长白山火山地震监测的现状和监测能力进行了讨论,并从基本的观测事实出发分析研究了长白山天池火山近年来的活动水平,对其目前的活动现状态进行了初步分析。  相似文献   

18.
以平果县这一典型岩溶生态脆弱区为例,依据1990、1995、2000及2002年的调查统计数据,对区域生态系统的生态足迹和生态承载力进行测算,并以测算结果为依据,对区域生态系统可持续发展状况进行评价。结果表明,在1990年、1995年、2000年、2002年,平果县区域生态足迹呈不断增加的趋势,人均生态足迹从0.8004hkm^2增加至1.4444hkm^2,净增加了0.644hkm^2;生态承载力总体也呈增长的趋势,2002年比1990年增长了26.83%,其增长值主要来源于森林(果园)面积的增加,而耕地和草地的面积却呈现负增长。区域生态承载力阈值很小,远低于广西区及全国的同期水平;除森林(果园)表现为轻微生态盈余外,耕地、草地、水域均表现为生态赤字,以致区域生态总体表现为较大的生态赤字,且呈逐渐增加趋势,表明区域生物生产土地面积的需求量已经严重超过区域生态系统的承载能力,区域可持续发展的前景不容乐观。[   相似文献   

19.
工程地质:十年回顾与展望   总被引:1,自引:0,他引:1  
在近十年,工程地质学科紧密结合国家战略需求和工程建设的科学技术难题,为国家超级工程建设提供了技术支撑,而且通过理论创新和技术研究,极大减少了因地质灾害而死亡的人数,取得了一大批代表性的理论成果,可以用三句话总结十年来工程地质学科的发展:“奠基超级工程、保障民生福祉、推动学科发展”。但是应当注意到,我国工程地质学的发展还远远不能适应国民经济发展和人民安居乐业的要求,打破学科壁垒,吸收相邻学科特别是现代地球系统科学以及技术科学的最新成果,加强工程地质人才建设,推动学科发展仍然任重而道远。  相似文献   

20.
Engineering and scientific approaches to design magnitude estimation are briefly revisited. Some defense is offered for use of annual maxima in design as if they were variables from a common distribution. However, to assume any particular form of distribution tail beyond the largest data value is not justifiable, regardless of the degree of data support over the main body of the distribution. An alternative approach to the design problem is suggested through use of parameter-free nonparametric estimation using the kernel method. Some simulation results are presented which suggest that the parameter-free approach is worthy of further development. A particular advantage of nonparametric methods is that competing estimators can be checked against parametric distributions, leading to a progressive improvement in estimator accuracy.This paper was presented (by title) at Engineering Concepts, MGUS-87 Conference, Redwood City, California, 13–15 April 1987.  相似文献   

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