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991.
地下管线是现代城市的生命线,是一个城市重要的基础设施,担负着信息传输,能源输送等工作,也是城市赖以生存和发展的物质基础。由于历史的原因,相当一部分地下管线无竣工资料,因此地下管线普查在当今的现代化建设中有着举足轻重的作用。下面就以2009年我单位开展的顺义区管线普查为例,并结合我这七年来的工作经验谈谈城市地下管线普查的方法。 相似文献
992.
城市地下管线信息系统的开发与应用 总被引:4,自引:0,他引:4
本文在分析城市地下管线信息系统发展现状的基础上,提出了一种新的管线信息系统开发模式,即成图系统加属性信息管理系统加图数连动机制。 相似文献
993.
994.
紫云自治县为全国重点扶持的特困县之一,21世纪来临之际贫困率仍高达26%,脱贫任务十分艰巨.由于贫困人口高度集中分布在五个贫困小区,区域性贫困现象突出.该文分析区情,从能力建设的战略角度,提出开发以优质杂交玉米、苡仁米为主的种植业,以山苍子、金银花、天麻为主的药材业,以生猪、黑山羊、黄牛为主的畜牧业,以大理石为主的建材加工业,以开发观光旅游资源为主的旅游业等五大优势产业.把四大优势农产品农业基地的建设、节水农业、小流域综合治理、异地开发、乡镇企业的投入和管理、观光旅游等作为重点扶持项目. 相似文献
995.
通过铬在包气带的垂直渗滤试验探讨了铬对地下水污染的机制,认识到地下水铬污染的主要途径是通过包气带渗入,铬在包气带中的垂直迁移性好,铬进入含水层后,在水动力条件及浓度的影响下,可发生运移—弥散作用,造成大面积地下水污染,严重影响生态环境。 相似文献
996.
Building period formulas in seismic design code are evaluated with over 800 apparent building periods from 191 building stations and 67 earthquake events. The evaluation is carried out with the formulas in ASCE 7‐05 for steel and RC moment‐resisting frames, shear wall buildings, braced frames, and other structural types. Qualitative comparison of measured periods and periods calculated from the code formulas shows that the formula for steel moment‐resisting frames generally predicts well the lower bound of the measured periods for all building heights. But the differences between the periods from code formula and measured periods of low‐ to‐medium rise buildings are relatively high. In addition, the periods of essential buildings designed with the importance factor are about 40% shorter than the periods of non‐essential buildings. The code formula for RC moment‐resisting frames describes well the lower bound of measured periods. The formula for braced frames accurately predicts the lower bound periods of low‐to‐medium rise buildings. The formula for shear wall buildings overestimates periods for all building heights. For buildings that are classified as other structural types, the measured building periods can be much shorter than the periods calculated with the code formula. Based on these observations, it is suggested to use Cr factor of 0.015 for shear walls and other structural types. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
997.
韩容畴 《广东海洋大学学报》1993,(2)
湛江某琼胶厂在生产初期出现产品颜色发黄,其原因是由于该厂使用了含铁地下水作为生产用水所致。湛江市区的地下水是属于第二类型含铁地下水,可对该类型的地下水进行深度处理,来达到除铁、提高产品质量的目的。 相似文献
998.
999.
为了研究土-结构相互作用对高层建筑地震响应数值模拟的影响.选择一栋具有地震观测记录的高层建筑(结构台阵)作为研究对象.利用Abaqus有限元软件和2009年姚安地震加速度记录,并假定了水平成层和有倾角成层的2种土介质模型.进行土-结构动力反应分析。结果表明:有倾角成层土-桩-结构相互作用模型的计算结果与观测资料相比有明显的放大现象,在NS方向体现的更加明显。这说明,就高层建筑的抗震分析而言,土介质模型对计算结果影响很大,在进行地震作用下土-结构地震响应分析时.土层模型应尽可能与真实土层相符。否则其计算结果会产生较大误差。 相似文献
1000.
Resat Ulusay Candan Gokceoglu Tamer Topal Harun Sonmez Ergün Tuncay Zeynal Abiddin Erguler Ozgu Kasmer 《Environmental Geology》2006,50(4):473-494
The Cappadocia Region of Central Anatolia having a very distinct culture is one of the attractive touristic sites of Turkey due to its spectacular and unique landforms and historical heritages. In this region, the structures carved into thick to massive tuffs survived and kept their original integrity for a number of centuries. Environmental and anthropological factors at the Cappadocia Region have been the main reasons for extensive subsurface and multi-purpose use in the past and present. In addition, thermal insulation properties of the tuffs make these rocks suitable for use in underground openings. The Kayakapi Neighborhood, located in the town of Urgüp, is one of the famous historical sites. This site is situated within the “Göreme National Park and the Rock Sites of Cappadocia” which was inscribed on the World Heritage List in 1985. In order to develop the tourism potential of this abandoned site while preserving its cultural and natural values, a natural environmental conservation and revitalization project was initiated. As an integral part of this project, in this study, environmental and engineering geological problems, including rock fall potential and stability of about 1,200 rock-hewn structures, were investigated and an inventory was prepared for the possible re-use of the underground openings and other structures at the site, and remedial measures were recommended. The assessments based on observations and experimental studies indicated that the tuffs do not show significant changes both perpendicular and parallel to layering, and discontinuities and rock weathering seem to be more important factors controlling the stability of rock-hewn structures. The major stability problems threatening the re-use of the openings are structurally-controlled block instabilities, overbreaks, and erosion and shearing of the pillars made of tuff. On the other hand, the area at the entrance of the site requires some protection measures such as the construction of a retaining wall, systematic bolting of rock slabs and removal of some blocks having rock fall potential. The inventory for the openings suggests that there are a number of openings that can be re-used after necessary remedial measures. 相似文献