电子平板测图软件EPSW在地籍测绘中的应用     

陈先伟  尹宏 《四川测绘》1999,22(4):176-179,170

当前计算机技术在测绘领域中的应用正迅速发展,在测图方面,传统的白纸测图因为手工在图纸上按一定比例尺绘制一菜,地物要素导致作业效率低下和原始数量数据精度受损。数字测图是以数字的形式表达地物特征点的全解析机助测图方法,它具有作业效率高,成图规范,原始测量数据精度无损伯的优点。  相似文献   

华北地区钻孔应力应变中短期预报指标和区域特征研究     

赵淑萍  冯志军 《高原地震》1999,(1)

经过长时间段（1969～1997年）,大区域（34°～42°N,110°～114°E）钻孔应力、应变台网异常时空扫描,得出的结论是：可把异常形态特征和异常区域特征作为中期或短期地震预报指标。  相似文献   

阿尔泰大型剪切弧形推覆构造系及其应变恢复     

曲国胜  张进江 《现代地质》1992,6(2):188-200

海西中晚期阿尔泰造山带中发育了一系列剪切弧形推覆构造系,平面上呈弧形,剖面上呈叠瓦状背驮式由北东向南西斜—逆冲,其成因是斜向的壳内叠积及受早期类拗拉谷楔形构造和斜—逆冲下盘边界的联合影响,喜马拉雅期推覆系重新复活。应变恢复表明现长为50Km的剖面其原长最小为266.7Km,最小缩短量为216.7Km,海西早期类拗拉谷的最小宽度为170Km,应变恢复结果与斜—逆冲模式一致。  相似文献   

An engineering geological appraisal of the Lakhwar Dam, Garhwal Himalaya, India     

Sanjeev Sharma  Tarun Raghuvanshi  Atul Sahai 《Engineering Geology》1999,53(3-4):381-398

A 204 m high solid concrete gravity dam is proposed across the River Yamuna in Garhwal Himalaya, India. It will be located on dolerite rocks which have been intruded into the slates of Chandpur Formation. The present study includes the evaluation of the dam foundation by means of drifts, drill holes, water pressure tests and abutment slope stability studies. The water pressure test indicate the necessity of providing a grout curtain below the dam foundation. The analysis of the dam abutments for stability using the Limit equilibrium method indicates that the right abutment slope is kinematically unstable for plane failure mode. The plane failure analysis of the right abutment slope was carried out by modifying the Hoek and Bray (1981, Rock Slope Engineering, 3rd ed., Institute of Mining and Metallurgy, London) technique of plane failure analysis. The analysis reveals that right abutment slope may become unstable during the stripping operation. Based upon the analysis a safe cut slope design for the abutments have been suggested. Subsurface exploration by means of cross drift and drill holes has indicated a sheared contact of slate and dolerite in the foundation area. To avoid the settlement of the dam along this shear zone precautionary measures are suggested.  相似文献   

构造流变计   总被引：18，自引：3，他引：15  

曾佐勋  樊春  刘立林  陈桂华  凌峰  彭振华 《地质科技情报》1999,18(4):14-18

根据构造形迹和应变式反演岩石流变性质的方法称为构造流变计,或简称流变计。目前提出的流变计主要有应变折射、能干层褶皱香肠构造、残斑翼尾样式。应变折射、能干层褶皱和香肠构造流变计已进入量化阶段。构造流变计 可用于研究不同尺度地质体的流变结构,也可用来研究地质体的流变学演化,具有很好的发展前景。  相似文献   

堤下爆炸法处理淤泥地基新工艺的理论、实验及工程应用(Ⅱ)桩对桩间抛石棱体下爆炸挤淤的动力响应     

杨振声  燕琳  张加华 《海洋工程》1999,17(2)

本文是堤下爆炸法处理淤泥地基新工艺的研究及应用的第二部分,着重介绍该工艺应用于桩间棱体的挤淤时,爆炸冲击波和淤泥、石块运动对桩的作用。计算和检测表明,桩体的安全是可以得到保证的。  相似文献   

Effects of horizontal strain in estimating specific storage and compaction in confined and leaky aquifer systems   总被引：6，自引：1，他引：5  

T. J. Burbey 《Hydrogeology Journal》1999,7(6):521-532

 Mathematical and numerical distinctions are made between developments of governing equations involving groundwater flow and granular displacement where (1) only vertical strain and no change in total normal load are assumed, and (2) such limitations are eliminated. The former is referred to here as the Jacob-Terzaghi method; the latter is referred to as the Biot method. Numerical comparisons of drawdown, compaction, and strain are made for hypothetical confined and leaky aquifer systems for one- and three-dimensional strain problems. Simulation results indicate that incorporation of horizontal strain results in reduced drawdowns. Vertical compaction for a specified stress distribution is greatly reduced when horizontal strain is invoked. The distribution of strain components indicates that approximately two-thirds of the total volume strain originates from horizontal compaction in pumped aquifers. Incorporation of horizontal strain also affects the distribution of flux through the overlying confining layer as a function of distance from the pumping well and may ultimately affect the interpretation of aquifer-test data. Received, January 1999 / Revised, May 1999, August 1999 / Accepted, August 1999  相似文献   

Convective instability of a boundary layer with temperature-and strain-rate-dependent viscosity in terms of 'available buoyancy'   总被引：2，自引：0，他引：2  

C. P. Conrad  & P. Molnar 《Geophysical Journal International》1999,139(1):51-68

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土质边坡剖面上动力响应异常点与潜在滑动面位置的关系研究          下载免费PDF全文

任自铭  冯仲林  殷世林 《地震工程学报》2009,31(1):21-25

通过数值分析对土质边坡动力响应规律进行研究,发现在土质边坡剖面上动力响应参数分布异常的地方跟通常认为的潜在滑动面有很好的对应关系,说明在坡体内发生较大剪应变处土体的动力特性可能已经发生改变,从而使动力传递异常.  相似文献   

Towards probabilistic seismic performance of vehicle-bridge interaction systems: From stochastic dynamic model to fragility analysis     

Peng Yuan  You Dong  Ruiwei Feng  Dan M. Frangopol 《地震工程与结构动力学》2023,52(1):88-110

This paper aims to assess the seismic fragility of vehicle-bridge-interaction (VBI) systems considering the effects of vehicle types, traffic conditions, and road surface qualities. A stochastic nonlinear mechanical model for the earthquake-VBI system is developed, and the fragility functions for the proposed VBI model are derived by considering the relevant probabilistic seismic demand parameters. On the basis of a typical four-span continuous prestressed concrete highway bridge in China, a complete numerical model for the VBI system is built considering multiple uncertainties from bridge and vehicle parameters, as well as the road surface qualities. A total of 120 real ground motion records with different combinations of magnitude-source-to-site distance (M-R) and earthquake intensity characteristics are selected. Meanwhile, 80 scenarios in terms of different combinations of vehicle types, vehicle speeds, and road surface irregularities are defined. In this context, 96,000 nonlinear time-history analyses are performed, and the developed fragility models are applied to the VBI system at both component and system levels. Results indicate that the fragilities of pier drift, bearing shear strain, and the overall VBI system increase with the increase of the vehicle weight or the decrease of the vehicle speed, while the vertical deck displacement is dominated by the vehicle weight. It is also found that the road surface quality has a negligible effect on both component and system fragilities.  相似文献