共查询到19条相似文献，搜索用时 125 毫秒
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指出了远海工程取水口建设在发电站后方,主体结构由预制管廊和预制泵井构成,安装底标高在水下5m左右,安装精度要求较高。以预制泵井安装施工为例,对预制泵井的起吊计算、水下安装工艺和深基坑稳定性计算进行了分析讨论,提出了施工方案,工程施工后满足了施工要求,保证了工程的顺利施工。 相似文献
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预应力钢筋混凝土T梁,因其跨度大、自重轻、结构简单、安装方便等优点,目前在国内高等级公路建设中被广泛采用。普通装配式钢筋混凝土简支桥梁,不但材料消耗多、且自重大,主粱片在自重和其它荷载作用下极易出现裂缝,影响桥梁结构的安全。因此,在桥梁跨度大于20 m,特别是跨度大于30m以上时往往采用预应力混凝土结构,即预应力混凝土T简支梁施工。根据在国道301线扎莱木德大桥梁场工程实例,从预制梁场的选址、施工现场场地硬化、制梁底座浇注、钢筋骨架加固安装、模板设计制作,到波纹管安装、混凝土浇筑、钢绞线的加工安装、张拉注浆、养生等,经过施工中不断的探索,详细阐述预应力混凝土T梁的预制过程施工技术。 相似文献
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工具式定型模板在框架、框架-剪力墙结构模板施工中被广泛采用。本文对其施工组合安装工艺进行了详尽的论述。 相似文献
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针对南方某些富水地层下的地铁施工问题,结合某地铁联络道冻结法施工的工程实例,采用低温盐水冻结法对富水地层进行冻结施工,分析了该案例中冻结施工所需要的设备、施工方案的确定以及监控量测的作用。结果表明:在冻结时间40d前后土体开始交圈,冻胀压力开始降低;50d后冻结壁厚度1.8m,土体平均温度-10℃,满足冻结指标,成功解决了由于地铁施工中土壤含水率较大而无法正常进行加固的问题。同时由于该工法对土壤加固属于临时加固且土体本身存在冻胀融沉现象,建议今后的研究重点放在此问题的防治措施上。本文案例中地铁联络道冻结法的成功应用,可供类似地下工程进行参考,具有一定的借鉴意义。 相似文献
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对变电站工程中电气设备安装技术的探讨——以深圳220kV红坳变电站为例 总被引：1，自引：0，他引：1
针对220 kV变电站施工组织设计及电气设备安装技术等相关问题,以220kV红坳变电站施工作为具体实例,对该工程概况、施工方案、主要工序施工方法及设备安装技术等内容进行阐述。在对该变电站施工组织设计经验总结的基础上,对变电站工程安装技术进行了深入探讨,希望能对同类型变电站施工组织设计提供借鉴和参考。 相似文献
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由于各种超前地质预报方法都存在一定的局限性,选择适宜的超前地质预报方法及地表探测方法相组合,可以提高超前地质预报的精确性与经济性。通过分析常用的超前地质预报方法及地表探测方法的优缺点,判断其适用范围,并在某引水工程实例中,根据其施工特点,洞内采用地震波法和激发极化法,洞外采用大地电磁法的长短结合、内外结合的探测方案,准确预报了掌子面前方80 m内的破碎、含水岩体及80～350 m的含水背斜构造,指导施工,有效避免了相关风险,提高了超前地质预报的精确性与经济性,可为综合探测方案的选择提供参考。 相似文献
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卷烟厂项目中大跨度厂房多采用网架结构体系，与网架结构体系对比，虽然采用大跨度钢桁架用钢量稍大，但能减少3m的层高，可以减少空调和采暖的能耗，从而达到节能的目的，获得长期效益。本文结合长春卷烟厂项目，根据反应谱法对屋盖结构在水平地震作用下的地震反应进行计算分析，并研究次应力及屋盖竖向支撑布置距离对桁架的影响。 相似文献
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移动模架在50m跨径现浇箱梁中的应用 总被引：1，自引：0，他引：1
根据移动模架在温州某桥50m跨径现浇箱梁施工中的应用情况，详细介绍了移动模架的构造、工作原理和现浇箱梁的施工工艺；通过利用移动模架进行跨径50m现浇箱梁施工的经验总结，指出了其在大跨径现浇箱梁施工过程中的经济性和施工质量及工期等方面的优越性；针对移动模架的技术要求，指出了其在中大跨径现浇箱梁中的应用前景。 相似文献
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The main objective of this study was to determine which property, of the six strength and stiffness properties used in structural timber design, was the most influential in the design of nail-plated roof trusses. Thirty recently completed nail-plated roof truss designs were randomly selected from three roof truss manufacturing plants and a total of 8 758 individual truss members were analysed for bending stress, shear stress parallel to grain, tensile stress parallel to grain, compression stress parallel to grain and deflection. The mean strength and stiffness capacity utilised of all the different design properties was well below 50% for all of the different dimension classes. Of all the individual strength properties, the mean bending strength capacity utilised per member was found to be the highest. The results of this study can be used for decision support related to wood property evaluation through? out the structural lumber value chain where roof truss members are the end products. 相似文献
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钢箱梁及钢桁架城市人行天桥对比分析 总被引：1，自引：0，他引：1
钢箱梁桥在我国城市人行天桥中应用广泛,其优点是线型美观,工厂预制装配式施工方便等。然而由于需要控制竖向自振频率,钢箱梁一般梁高过高,造成压抑感强,两侧梯道过长等缺点也不容忽视,因此钢桁架桥在城市人行桥中也是一种可以广泛普及的桥型,本文对相同跨径的两种桥型就结构用钢量、竖向自振频率、施工性、梯道爬高等方面进行了综合对比。 相似文献
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Philip L Crafford 《Southern Forests》2016,78(1):61-71
South Africa is a timber-scarce country that will most probably experience a shortage of structural softwood lumber in the near future. In this study the concept of using young, green finger-jointed Eucalyptus grandis lumber was evaluated for possible application in roof truss structures while the timber is still in the green, unseasoned state. Drying will occur naturally while the lumber is fixed within the roof truss structure. The objectives of this study were (1) to investigate the strength and stiffness variation of the finger-jointed E. grandis product in both the green and dry state for different age and dimension lumber, (2) to investigate the variation in density, warp and checking in the lumber when dried in a simulated roof-space environment and (3) to evaluate the potential of this finger-jointed product as a component in roof truss structures. Green finger-jointed E. grandis lumber of ages 5, 11 and 18 years and dimensions 48×73?mm and 36×111?mm from Limpopo province were evaluated. The study showed that the young finger-jointed E. grandis timber had very good flexural, tensile parallel to grain, and shear properties in both the green and dry state. The mean and characteristic modulus of elasticity and modulus of rupture values of the finger-jointed E. grandis product were higher and the variation lower in comparison to currently used South African pine sources. The tensile perpendicular to grain and compression perpendicular to grain strength did not conform to SANS requirements for the lowest structural grade (S5). Both tree age and product dimension were sources for variation in the physical and strength properties. Based on the results from this study the concept of producing roof trusses from green, finger-jointed young E. grandis timber has potential. 相似文献
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分析了屋面防水卷材渗漏的原因:如外界环境因素的影响、施工方法不当的影响、屋顶本身构造及使用过程的影响等;并对其渗漏常见现象提出了解决方法. 相似文献