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61.
National Persian Gulf Bridge is a communication route between Bandar Abbas port and Qeshm Island located on the southern border of Iran. This causeway has important role for facilitating the transportation system between Qeshm Island and mainland, i.e., Bandar Abbas. Based on geotechnical and geological site investigation records, the bridge is located on the deposits with high seismic possibility and subsequently significant dynamic loading. Therefore, adequate substructure design of this bridge as an offshore project is realized as a major requirement. The geophysical and geotechnical investigations have been done to obtain the subsoil characteristics of the project site. For this purpose, 18 boreholes have been performed to do in situ tests and extract samples for laboratory testings. Data synthesis indicates that in the zones close to Qeshm Island and in the deeper parts of the sea, the strata is made of clay with loose sands and some depths, with silty sands. Hence, instability issues, including the low bearing capacity and the high differential settlement, are significant aspects in analysis and design of substructure for this project. Also, in this paper, the subsoil conditions have been studied from in situ tests such as standard penetration test (SPT) and cone penetration test (CPT) results in order to achieve an appropriate foundation system. Moreover, the necessity of the ground improvement of the site has been investigated to propose an efficient technique for safe and secure construction. Based on the analysis and methods screened, the vibro-replacement method is considered as a suitable and efficient ground improvement method for this project.  相似文献   
62.
彭玉鲸 《吉林地质》2001,20(4):88-97
地球科学中大地构造理论假说争论的历史经历了山脉臆说的“实在论”与“唯名论”的探索、“塌陷说”与“隆起说”对立时期以及受“形而上学”和“自然哲学”的影响这一过程。“收缩说”统治时期,“机械唯物主义”阻碍了“自然辩证法”的指导;“活动论”兴起后,并未找到先进的地学哲学武器。中国古代有机论自然观蕴藏了丰富的地学哲学思想-有机论辩证唯物主义的天地生整体自然观。“立地之道,曰柔与刚”,“合乎谓之坤,辟乎谓之乾,一合一辟谓之变”,“刚柔相摩,八卦相摩,八卦相荡”等精辟论述。早已从地质哲学高度,把“威尔逊旋回”、“开合运动”等大地构造假说涵蓄其内。大地构造理论的未来发展必然由此获得新的启迪。  相似文献   
63.
考虑非线性的建筑物地基地震液化简化分析方法   总被引:2,自引:0,他引:2  
本文在建筑物地基地震液化总应力简化判别方法的基础上,考虑地基土壤的剪切非线性及饱和砂土Martin非线性孔压增长模型,提出了估计建筑物地基孔压增长的简化分析方法,这一方法可用来判别地基的初始液化问题。  相似文献   
64.
根据贫金属星个别重元素丰度的观测值和太阳系重核素的r过程和s过程分量的丰度分布,计算了贫金属星HD203608和HD211998的重元素丰度并与观测进行了比较。结果表明,太阳系纯r过程和s过程元素丰度均不能拟合出这二颗样品星的丰度观测值,而应同时考虑r过程和s过程的贡献  相似文献   
65.
低丘红壤深层水分的CASCADE模型应用与管理   总被引:1,自引:0,他引:1  
景元书  张斌  赵其国  Zepp H  Thimm A 《山地学报》2003,21(4):461-465
低丘红壤深层水分对建立合理的耕作制度和旱季作物水分调控有重要意义。花生地定位试验实测数据表明:旱地土壤水分垂直梯度变化趋势基本表现为增长型,土壤含水量受降雨影响在40cm土层旱季明显大于雨季。采用CASCADE模型模拟了不同年型低丘红壤地区花生地土壤含水量的动态过程,各层次模拟值与实测值的平均绝对偏差<4 7%,模型可用于分析红壤水分的季节性变化规律和采取抗旱措施。还针对水分利用存在的问题,从工程措施、生物措施和生产措施三方面进行红壤旱地水分资源的有效管理,提高红壤地区降水资源与深层水分的利用率。  相似文献   
66.
利用欧拉反褶积法估计二度磁性体深度与位置   总被引:7,自引:0,他引:7  
史辉  刘天佑 《物探与化探》2005,29(3):230-233
为了利用欧拉反褶积进行快速计算,提出了多个大小不同的滑动窗口进行多次覆盖的算法,对高精度磁测剖面逐点反复计算,并根据统计学原理从大量计算结果中剔除坏解,保留合理的解;还根据2-D模型讨论了结构指数与欧拉反褶积的结果的关系。将该方法应用于我国西北某地区的高精度航磁资料处理,获得较好的地质效果。  相似文献   
67.
Solar evaporation studies of subsoil brines from three different locations of Gujarat State in India were undertaken. Evaporation of brines from their initial densities to 29-30°Be’ density was studied and the data were compared with those of sea brine. From the experimental data, the change in the quality of salts crystallized at various density levels with changing ionic composition of brines is explained theoretically and the ionic composition of an ideal brine and proper density ranges for the recovery of high quality salt are identified. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
68.
本文通过对天水市秦州、麦积两区砂砾石地基进行大量颗粒分析、动力触探、灌砂法试验及人工回填打入预制桩、人工挖孔灌注桩静载荷试验,并对其各项试验结果进行统计,系统地总结了天水城区砂砾石的分布特征、颗粒组成、物理力学性质;并通过粒径直方图统计分析阐明了藉河流域颗粒级配明显好于渭河流域,承载力特征值亦高于渭河流域的几个关键问题,并通过对工程实例的试验检测,对涉及的砂砾石地基的承载力特征值及变形模量,桩的极限端阻力标准值、极限侧阻力标准值应用实际问题进行了对比、讨论和分析,因此对工程质量的检测和设计应用有着重要意义,可供类似工程参考。  相似文献   
69.
BOOK REVIEWS     
Book Reviewed in this article: Rabat: Urban Apartheid in Morocco . Janet Abu -Lughod . Marketplaces in a Developing Country: The Case of Western Nigeria . Isaac Ayinde Adalemo . Farming Development and Space: A World Agricultural Geography . Bernd Andreae . Section and Party: A Political Geography of American Presidential Elections, from Andrew Jackson to Ronald Reagan . J. Clark Archer and Peter J. Taylor . Women and Space: Ground Rules and Social Maps . Shirley Ardener , ed. European Progress in Spatial Analysis . R. J. Bennett , ed. The Origins of Academic Geography in the United States . Brian W. Blouet Geographic Perspectives on Global Problems . Ronald Reed Boyce . Seasonal Dimensions to Rural Poverty . Robert Chambers , Richard Longhurst and Arnold Pacey eds. The New Nationalism and the Use of Common Spaces: Issues in Marine Pollution and the Exploitation of Antarctica . Jonathan I. Charney , ed. Communications Tomorrow: The Coming of the Information Society . Edward Cornish , ed. The Design of Suburbia . Arthur Edwards . Explorer on the Northern Plains: Lieutenant Gouverneur K. Warren's Preliminary Report of Explorations in Nebraska and Dakota in the Years 1855–56–57. With an Introduction by Frank N. Schubert . The Changing Climate: Responses of the Natural Flora and Fauna . Michael J. Ford . Essentials of Physical Geography . Robert E. Gabler , Robert J. Sager , Sheila Brazier , and Daniel L. Wise. The Road to Jaramillo . William Glen . Valued Environments . John R. Gold and Jacquelin Burgess , eds. Proximity and Preference: Problems in the Multidimensional Analysis of Large Data Sets . Reginald G. Golledge and John N. Rayner , eds. A Search for Common Ground . Peter Gould and Gunnar Olsson , eds. Geography: Its History and Concepts . Arild Holt -Jensen . A Population Geography . Huw R. Jones . The Human Mosaic: A Thematic Introduction to Cultural Geography, 3rd ed. Terry G. Jordan and Lester Rowntree . Urban Social Geography: An Introduction . Paul Knox . The Anatomy of Job Loss: The How, Why and Where of Employment Decline . Doreen Massey and Richard Meegan . The Information Society as Post-Industial Society . Yoneji Masuda . Map Librarianship, 2nd ed. Harold Nichols . India: Cultural Patterns and Processes . Allen G. Noble and Ashok K. Dutt , eds. The God that Limps: Science and Technology in the Eighties . Colin Norman . Geography: An Introductory Perspective . Robert E. Norris , Keith D. Harries and John D. Vitek . The Politics of Technology Assessment . David M. O'Brien and Donald A. Marchand . Ethnic Segregation in Cities . Ceri Peach , Vaughan Robinson and Susan Smith , eds. Churches and Church Membership in the United States, 1980 . Bernard Quinn , Herman Anderson , Martin Bradley , Paul Goetting and Peggy Shriver . Energy in Australia: Politics and Economics . Hugh Saddler . Development from Above or Below? The Dialectics of Regional Planning in Developing Countries . Walter B. Stóuhr and D. R. Fraser Taylor , eds. Human Impact on the Ecosystem . Joy Tivy and Greg O'Hare . Plants and People: Vegetation Change in North America . Thomas R. Vale . The Mapmakers: The Story of the Great Pioneers in Cartography from Antiquity to the Space Age . John Noble Wilford .  相似文献   
70.
利用遥感、DEM、基础地理信息、土地利用变更调查、社会经济统计等各类数据和专题图件,以平江县为例,构建湖南典型贫困区土地生态状况综合评估体系,对平江县土地生态状况进行综合评估,并计算各个元指标障碍度。结果表明,平江土地生态质量总体较好,大部分地区表现为优良状态,土地生态质量空间差异性较大,在空间上呈现北低南高、西低东高的趋势。影响平江县和各个乡镇土地生态状况的主要障碍因子为湿地比例、林地年退化率、土地利用类型多样性指数、耕地比例、植被覆盖度,个别乡镇的主要障碍因子还包括水面比例和人口密度。通过对平江县土地生态状况进行综合评估与分析,寻找影响其土地生态健康发展的主要障碍因子,提出相关建议,以实现土地可持续利用,为湖南典型贫困区土地生态状况评估提供科学研究方法。  相似文献   
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