共查询到20条相似文献,搜索用时 765 毫秒
1.
2.
3.
阮小林 《中国建筑金属结构》2014,(7):54-57
<正>广东合和建筑五金制品有限公司是国内数一数二的建筑五金生产企业,1981年成立。从当年的合和塑胶厂到今天的合和集团,经过三十多年的发展,合和作为一家民营企业已经形成了自己独有的企业文化,即合和文化。通过合和文化,合和集团逐步完善自我,以合作共赢,和谐发展 相似文献
4.
5.
利用有限元方法研究钢筋混凝土桁架式转换层在自重载荷和地震载荷作用下的变形和应力分布。以某综合楼为例,采用空间细长梁单元BEAM4和考虑剪切效应的空间梁单元BEAM188分别建立考虑上层结构和底层结构的桁架式转换层有限元模型。在顶部和底部分别施加含有位移约束条件的载荷条件和位移边界条件,计算获得自重和地震载荷作用下不同单元和边界条件下结构的变形和应力。讨论了不同单元和不同边界条件对结果的影响。研究表明梁单元BEAM4和BEAM188给出的结果差别不大,自重引起的内力是主要成分。同时讨论了模型选择应该注意的问题和如何降低转换层最大内力的方法。 相似文献
6.
2010年上海世博会印度馆的主展区拥有世界上最大的竹结构穹顶。整个印度馆包含一个二元空间——穹顶和表演前庭。潜在的二元性设计是对印度自身的隐喻,表现在庭院和穹顶两个空间:分别代表了热带城市独特的开放和封闭、无限和有限、非正式和正式;也代表了集市和庙宇、农村和城市、过去和未来。 相似文献
7.
8.
9.
10.
11.
针对堆土加卸载与基坑开挖叠加效应导致既有地铁隧道变形较大的问题,建立考虑加卸载叠加效应影响的三维空间分析模型,研究不同堆土加卸载叠加基坑开挖卸载模式对邻近地铁隧道变形规律的影响,探讨隧道在堆土加载、移土卸载再叠加基坑开挖下的变形规律。结果表明:正上方堆土加卸载对隧道的竖向位移影响较大,是侧向堆土加卸载的3倍~5倍; 在经历堆土加卸载后,隧道会残留不可忽视的变形,其残留竖向位移约为加载后位移的62%; 堆土加卸载叠加侧方基坑开挖时,隧道变形受基坑开挖深度的影响较大,大于隧道埋深的开挖阶段会加剧隧道变形; 4种叠加模式中,正上方堆土加卸载-侧方基坑开挖卸载隧道最终竖向位移最大,约17 mm,侧方堆土加卸载-异侧基坑开挖卸载隧道最终水平位移最大,约8 mm,邻近隧道施工时应充分考虑叠加效应的影响,尽量避免这两种情况。 相似文献
12.
13.
为改进钢筋骨架质量自动检查方法,提出了基于点云的钢筋骨架中钢筋数量和钢筋间距的自动检查算法。该算法在获取钢筋骨架实际点云和设计点云的基础上,首先对这两片点云分别进行降采样,以得到空间密集程度相同的钢筋骨架实际点云和设计点云; 其次,对降采样后的钢筋骨架实际点云和设计点云使用基于主成分分析(PCA)的方法进行粗配准。由于粗配准后的钢筋骨架实际点云和设计点云的配准精度较低,无法直接用于钢筋数量和钢筋间距的检查,对粗配准后的钢筋骨架实际点云和设计点云进行精配准。最后,基于精配准得到的钢筋骨架实际点云和设计点云,依次对钢筋骨架中的钢筋数量和钢筋间距进行检查。结果表明:精配准后的钢筋骨架实际点云和设计点云的配准精度较高,可以用于钢筋数量和钢筋间距的检查; 该算法对钢筋数量检查的准确率为100%,对钢筋间距检查的准确率为80%; 应用该算法可以有效提高复杂钢筋骨架中钢筋数量和钢筋间距检查的效率,降低人工成本。 相似文献
14.
Harald Budelmann Alexander Holst Hans‐Joachim Wichmann 《Beton- und Stahlbetonbau》2009,104(6):330-339
Magnetoelastic Measurement of Prestressing Force in Civil Structures The knowledge of the tensile force of prestressing steel elements and its reliable and non‐destructive determination are of essential importance for the assessment of the structural health condition of prestressed concrete structures and tie‐back systems in terms of structural safety, serviceability and durability. For the evaluation of the prestressing force in steel tension members, the measurement technique presented in this contribution is using the magneto‐elastic effect (ME‐effect) of ferromagnetic materials. This effect describes the reverse‐proportional correlation between the mechanical stress and the magnetic properties of ferromagnetic materials. The cylindrical coiled sensors pushed over the tendon and the measuring device developed and practically optimized at the iBMB/MPA of the TU Braunschweig enable a fast and reliable measurement of the prestressing steel force after an initial calibration. In this contribution first the state of the art of prestress measurement techniques for steel tension members is presented. Afterwards, the ME‐measuring method with the basics and merits of magneto‐elastic prestressing force identification is shown. Further recent research results as well as several building applications will be discussed. 相似文献
15.
秦淑玲 《建筑科学与工程学报》1993,(2)
建筑是一部人类文明史,建筑装饰艺术是其中最精美的语言,它记载着科学技术的发展和文化艺术的进步,它描绘出风土人情与时代风尚。本文主要论述了建筑外形式装饰艺术的涵义及设计要点,对建筑装饰艺术的形态构成、造型与装饰、装饰的视觉效应以及建筑外形式装饰艺术的个性和设计中应注意处理好的关系进行了讨论。 相似文献
16.
为增强装配式建筑产业链供应链自主可控力,保障装配式建筑产业链供应链安全稳定,采用文献梳理与实际调研结合法,贯穿全生命周期时空链,阐释装配式建筑产业企业链、供应链与价值链内涵及相互关系,进而构建装配式建筑产业链供应链自主可控力评价体系,采用COWA-DEMATEL法分析其自主可控力影响因素的综合中心度及其原因、结果效用,并从科技自主性、组织安全性与产业脆弱性3个方面提出了改善建议。结果表明:装配式建筑企业链属结构单元层面,价值链属结构目标层面,供应链属结构运行层面,三者存在相互作用、相互依存关系; 核心技术水平、外部环境波动、信息可控能力、合作协同程度、组织应急能力对装配式建筑产业链供应链自主可控力提升具有重要影响作用; 外部环境波动、资金自主水平、人员综合素质为影响装配式建筑产业链供应链自主可控力水平的主要原因因素,而产品安全水平为影响装配式建筑产业链供应链自主可控力水平的主要结果因素。 相似文献
17.
为分析不同规范中混凝土梁桥竖向温度梯度模式的差异,评估竖向温度梯度效应对混凝土梁桥的影响程度,总结了不同国家和行业规范中混凝土梁桥的竖向温度梯度模式,从梯度曲线形式和温度基数取值两方面讨论了效应计算结果的差异。选取了20多座不同结构体系、跨径和截面形式的混凝土梁桥,计算了在包括桥梁变形和截面应力在内的2种典型的竖向正温度梯度作用下的各项效应,与自重和汽车作用产生的效应作了对比。结果表明:不同规范的竖向温度梯度模式在梯度曲线形式和温度基数取值方面存在显著差异,它们对温度效应计算结果具有同等程度的影响; 顶部温差的影响深度越大,桥梁的变形和次生弯矩越大,考虑底部升温段时截面下缘有更大的自压应力; 不同的铺装层类型和气候条件造成桥梁温度基数取值存在差异,进而导致温度效应可能相差1.5倍~2.0倍; 相同结构体系和截面形式的中小跨混凝土梁桥随着跨径增大,自重效应占比增加,汽车和温度效应占比减小,但是温度和汽车效应的相对比例基本保持不变; 结构体系和跨径相同时,T梁的温度效应占比要比空心板和小箱梁高出0.6%~16.5%; 温度效应在一些效应类型中占有很大比例,温度作用引起的中小跨简支梁桥的变形和截面上缘应力能与自重和汽车效应相近,引起的中小跨连续梁桥的截面上缘应力能超过自重和汽车效应甚至两者总和,墩顶截面下缘应力能与自重和汽车效应相当,引起的大跨径连续箱梁桥截面上缘应力能超过汽车效应的数倍; 若考虑铺装层类型和气候条件的影响,在温度基数取值较大的梁桥上,温度效应占比可能更高。 相似文献
18.
The paper considers methods of procurement for the construction of water- and sewage-treatment works other than the traditional use of the ICE 5th Edition Conditions of Contract and Bills of Quantities. This is as a consequence of the speed at which schemes are currently required within the water industry.
The paper particularly focuses on the use of target contracts, using the Institution of Chemical Engineers'Green Book form, and considers various types of target. It also discusses the form which tender documents may take, and how targets may be calculated.
Tendering procedures, including the use of two-stage tenders and negotiated targets, are considered, as are the procedures for cost monitoring and the financial management of the contract. Finally, the role of the engineer and quantity surveyor is considered. 相似文献
The paper particularly focuses on the use of target contracts, using the Institution of Chemical Engineers'Green Book form, and considers various types of target. It also discusses the form which tender documents may take, and how targets may be calculated.
Tendering procedures, including the use of two-stage tenders and negotiated targets, are considered, as are the procedures for cost monitoring and the financial management of the contract. Finally, the role of the engineer and quantity surveyor is considered. 相似文献
19.
John Aitchison 《Landscape Research》1996,21(1):89-97
This paper considers the nature and significance of town and village greens within the landscape of England and Wales. It reflects on problems of definition and on the limited availability of data concerning the origins and geographical distribution of greens. The paper draws attention to the registration of greens following the Commons Registration Act 1965, and summarizes information collated from the registers subsequently prepared by local authorities. Details of numbers of greens and their spatial density at county level are presented, and reference is also made to rights of common on greens, and to the ownership of the greens themselves. 相似文献
20.
K. N. Remani E. Nirmala S. R. Nair 《The International journal of environmental studies》2013,70(4):285-295
One of the striking features of Kerala state is the continuous chain of lagoons or backwaters existing along the coastal region. The backwaters support rich and diverse life forms and provide crucial nurseries for shrimps and fishes as well as habitat for oysters, clams and mussels which later enrich the ocean and make Kerala the principal exporter of marine products amongst the states of India. The shallow fringes of the backwaters and the channels drawn from them are used for retting of coconut husk. It adversely affects the productivity of the backwaters and is harmful to marine fisheries. The retting of coconut husks in backwaters is brought about by the pectinolytic activity of micro organisms especially bacteria fungi and yeasts degrading the fibre binding materials of the husk and liberating large quantities of organic matter and chemicals into the environment, including pectin, pentosan, tannins, polyphenols, etc. Consequently hydrogen sulphide, phosphate and nitrate contents increase while dissolved oxygen and community diversity of plankton decrease in the ambient waters during the retting process. The present study is to evaluate pollution due to coir retting activity and its influence on quality of water and estuarine flora and fauna. 相似文献