高层建筑结构抗震设计中鞭梢效应的分析     

杨佑发  袁政强  敬登虎 《世界地震工程》2004,20(1):85-89

将钢筋混凝土结构离散为能模拟梁、柱、墙抗震性能的单元，采用串并联刚片系振动模型，体现空间各构件的协同工作，采用改进的Wilson-θ法。对鞭梢效应在高层建筑结构抗震中的影响作详细分析，做到合理利用鞭梢效应，从而可以解决高层建筑物中层间位移起决定性作用的问题，达到合理、经济的效果。  相似文献   

Monitoring of weathering and conservation of building materials through non-destructive X-ray computed microtomography     

V. Cnudde  P. J. S. Jacobs 《Environmental Geology》2004,46(3-4):477-485

X-ray computed microtomography (µCT) is a promising non-destructive imaging technique based on measurements of the attenuation of X-rays. It provides information on the internal structure of small samples with a maximum resolution of 10 µm. For this study, two porous local natural building stones, the sandstone of Bray and the limestone of Maastricht, were selected. Possible applications of the µCT-technique for qualitative monitoring of changes comprise (1) to non-destructively determine porosity based on 3-D images, (2) to visualise weathering phenomena at the micron-scale, (3) to understand the rationale of weathering processes, (4) to visualise the presence of water repellents and consolidation products, (5) to monitor their protective effects during decay in order to understand the operating mechanisms and (6) to provide advise on the suitability of products for the treatment of a particular rock type. The µCT-technique proves to be a powerful monitoring tool for the future as the combination of 3-D visualisation and 3-D data provide new insights that could optimise conservation and restoration techniques of building materials.  相似文献   

Explaining complexities of environmental management in developing countries: lessons from the Fiji Islands     

Jane Turnbull 《The Geographical journal》2004,170(1):64-77

Development assistance agencies have long urged developing countries to adopt environmental management techniques used in industrialized countries. They have ascribed shortcomings in the way developing states use those techniques to insufficient training, environmental matters being poorly integrated into economic decision making, other institutional weaknesses and lack of capacity. These reductionist explanations ignore the influence that socio-political and economic factors may have on state environmental management. They afford only a limited understanding of environmental practice in the Fiji Islands, a South Pacific archipelago and republic. The attempts of Fijian chiefly élite to maintain their power base – achieved through political participation in the state and economic development activities as much as through maintaining the communal system – shape the state's environmental management practices. Those practices have far less rational and democratic bases than one would expect either from the underlying logic of the techniques used (such as environmental impact assessment, environmental planning and protected areas), or from the way those techniques are applied in western, industrialized countries.  相似文献   

基于航空立体影像对的复杂房屋三维拓扑重建   总被引：1，自引：1，他引：1  

邵振峰  李德仁  程起敏 《武汉大学学报(信息科学版)》2004,29(11):999-1003

对利用航空影像对重建复杂房屋三维模型进行了研究，提出了拓扑链、外拓扑和内拓扑的概念，分析了复杂房屋的内拓扑和外拓扑的三维重建，构造了复杂房屋的三维拓扑数据模型。基于此模型设计了双向搜索算法，用于自动构建复杂房屋的三维拓扑面，从而实现了复杂房屋的自动三维拓扑重建。实验证明，本文提出的双向搜索算法是很稳健、高效的。  相似文献   

一种获取大比例尺建筑物立面影像的方法   总被引：3，自引：0，他引：3  

冯文灏  侯文广  张纯连 《武汉大学学报(信息科学版)》2005,30(8):673-676

提出了获取建筑物大比例尺立面影像的一种理论与方法。根据数字相机倾斜影像,利用建筑物外观的几何条件与约束条件,按照透视变换原理,导出相应关系式,直接获取相同主距的“平行影像”。随后,依据最少的实地控制,将平行影像放大到给定比例尺数字城市中。该方法加快了车载系统大比例尺建筑物立面影像的获取过程,不受建筑物高度的影响,并可用于机载、固定站和人工方式等多种作业模式。  相似文献   

黄土地区农村民房生土建筑墙体材料抗震性能试验研究   总被引：13，自引：2，他引：13       下载免费PDF全文

王峻 《地震工程学报》2005,27(2):158-162

对西北黄土地区农村民房生土建筑墙体材料的主要类型进行了物理力学性能和动力特性的试验研究,给出了黄土和黄土状亚粘土的夯筑墙、土坯等样品的抗压、抗折、抗剪强度以及动弹性模量和阻尼比等参数,对比分析不同生土建筑墙体材料和成型方式的强度和抗震性能。  相似文献   

ECOLOGICAL AND SOCIO-ECONOMIC REHABILITATION IN THE KARST OF SOUTHWEST CHINA     

Cai Yunlong Department of Geography  Peking University  Beijing People''s Republic of China 《地理学报(英文版)》1997,(2)

Ｉ.ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅａｃａｄｅｍｉｃ,ｓｃｉｅｎｔｉｆｉｃａｎｄｐｏｌｉｃｙ-ｍａｋｉｎｇｃｏｍｍｕｎｉｔｉｅｓｈａｖｅｆｏｃｕｓｅｄｃｏｎｓｉｄｅｒａｂｌｅａｔｔｅｎｔｉｏｎｏｎｔｈｅｃｏｎｃｅｐｔｏｆｓｕｓｔａｉｎａｂｌｅｄｅｖｅｌｏｐｍｅｎｔ.ＦＡＯ(1988)ｄｅｆｉｎｅｓｓｕｓｔａｉｎａｂｌｅｄｅｖｅｌｏｐｍｅｎｔａｓ”ｔｈｅｍａｎａｇｅｍｅｎｔａｎｄｃｏｎｓｅｒｖａｔｉｏｎｏｆｔｈｅｎａｔｕｒａｌｒｅｓｏｕｒｃｅｂａｓｅ,ａｎｄｔｈｅｏｒｉｅｎｔａｔｉｏｎｏｆｔｅｃｈｎｏｌｏｇｉ…  相似文献   

晋江磁灶镇建筑陶瓷工业可持续发展初探     

翁发春 《地域研究与开发》1997,16(4):55-58

通过分析磁灶镇建筑陶瓷工业在迅猛发展中存在着环境污染，科技落后，产品结构不合理等一系列问题后，提出了污染型瞳可持续发展的新思路。  相似文献   

高层建筑电梯平衡重体系的动力特性与地震反应分析     

吴波  李惠 《地震工程与工程振动》1995,(3)

本文在文献[2,1]所建立的平衡重体系运动方程的基础上,对高层建筑电梯系统中平衡重体系的动力特性进行了探讨,给出了求解该体系自振频率的近似方法,通过对一幢14层建筑内的平衡重体系进行的大量地震反应分析,研究了其动力反应沿建筑物高度变化的一般规律,给出了最大反应所处的位置。本文的工作为实施和推广文献[1]所提出的平衡重体系的抗震控制措施奠定了理论基础。  相似文献   

The application of spatial data processing to land use conflict resolution in the lal lal water catchment of the Ballarat growth corridor: a case study from chapter one of the Buninyong planning scheme     

I. A. Allan  J. A. Peterson 《The Australian geographer》1993,24(2):76-88

Land use conflict within the Lal Lal Water Catchment is between landowners, the Shire, the Water Board and those directing regional pressures for development. It is exacerbated by inconsistency in building permit appraisal outcomes. The deliberations involved would clearly have benefited from access to spatial data sets through use of a Geographical Information System (GIS) during applications appraisal, in that inconsistencies are most obvious when mapped in relation to the criteria applied. GIS methodologies would ensure that information of a high standard was produced. Three strategic points are identified for the implementation of GIS: at the planning scheme formulation stage; the permit application stage; and the formal conflict resolution stage. Reference to GIS at the first two stages presupposes the existence of a local government area (LGA) spatial data base and a GIS/LIS that can output overlay maps. Application of GIS at the third stage is somewhat ‘after the event’. This study suggests that without such a regional review of the spatial patterns of permit appraisal criteria (including overland flow modelling) each appeal or negotiation is likely to yield an outcome that is inconsistent in relation to other cases. An LGA planning office maintaining a GIS with all layers relating to these criteria will have assembled its spatial data according to the requirements of its planning scheme and will make most use of it in a GIS at the permit appraisal stage.  相似文献