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结合SET 1X全站仪在雅泸高速公路菩萨岗隧道贯通测量中的实际应用,阐述隧道贯通测量所采用的方法及各项技术措施,从而确保隧道精确贯通. 相似文献
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大跨径钢管混凝土拱桥减震控制装置参数的研究 总被引:1,自引:0,他引:1
大跨度桥梁结构的减震控制研究对于桥梁结构的抗震安全具有重要意义。本文以主跨368m的茅草街大桥为研究对象,基于ANSYS建立了该桥的三维有限元模型,并采用子空间迭代法分析了该桥的动力特性。在此基础上进行了大跨度钢管混凝土拱桥的地震响应及减震控制研究,重点进行了弹性连接装置和粘滞阻尼器减震效果的参数敏感性分析,并对比分析了不同位置布设减震装置时的效果。结果表明,纵飘振型对该桥肋纵向相对位移的贡献最大;弹性连接装置和阻尼器均能有效减小地震作用下该桥的肋梁纵向相对位移;综合考虑各关键部位的地震响应时,同时采用两类减震装置并将其分散布置时的减震效果最佳。结论可供大跨度中承式钢管混凝土系杆拱桥的抗震设计参考。 相似文献
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A new type of steel moment resisting frame with bottom ? ange friction devices (BFFDs) has been developed to provide self-centering capacity and energy dissipation, and to reduce permanent deformations under earthquakes. This paper presents a numerical simulation of self-centering beam-column connections with BFFDs, in which the gap opening /closing at the beam-column interfaces is simulated by using pairs of zero-length elements with compression-only material properties, and the energy dissipation due to f... 相似文献
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Along with the consumption increase of the petroleum products,more countries have transferred their attentions to the offshore fields,especially the deepwater oil and gas reserves.For deepwater exploitation,the risers must be installed to act as the conduits connecting surface platforms to subsea facilities.In this paper,the typical risers sorted by different classes are introduced,and the correspondent installation methods are presented.By investigating the recent projects performed in the deepwater hot spots,and combining the challenges of HYSY201 for riser installation,a lifting device developed for assisting riser installation is proposed and detailed to satisfy the installation of deepwater risers in the LW3-1 Gas Field of in the South China Sea.Tests on both the functions and performances of such a new system exhibit the satisfaction of meeting all challenging requirements of HYSY201 for application to riser installation in waters up to a depth of in the South China Sea. 相似文献
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《Geomechanics and Geoengineering》2013,8(1):73-85
Bricks made of compacted sand–bentonite mixture are considered as a possible engineered barrier to isolate high-level radioactive waste at great depth. This work is aimed at investigating some specific effects related to the presence of discontinuities at the contact between the bricks and the excavation wall. In order to do this, an experimental device was developed in the laboratory. The model is made up of a specially designed infiltration cylinder which allows the precise definition of a planar discontinuity between the compacted specimen (a sand–bentonite mixture made up of sand and Kunigel clay from Japan) and a metal wall. During hydration and subsequent specimen swelling, the planar wall is filled, resulting in a healing process. Three total pressure gauges placed along the wall allow a detailed observation of the increase in total stress against the wall. After different periods of swelling, the maximum resistance of the specimen–wall interface to pressure was tested by imposing a pressure increase through a porous stone placed at one end of the cylinder. It was found that the maximum pressure supported by the interface is a function of the initial thickness of the discontinuity and the initial density of the specimen. It was also found that the maximum sustainable pressure depends linearly on the elapsed time. These results are of interest for optimizing water infiltration procedures in either mock-up tests or real disposal systems. If the maximum sustainable pressure at the interface is known, it is possible either to ensure homogeneous hydration of a mass of bricks by respecting the maximum injection pressure limit or to accelerate hydration by forcing water paths along the discontinuities. 相似文献
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地热资源储量丰富,分布广泛,开发前景广阔。但是在现有地热钻井技术条件下进行地热开发的周期长、成本高,所以亟待钻井技术的突破使巨大的地热资源得到经济有效地开发。碎裂钻井技术是一种采用了新的钻井原理的钻井技术,其能够有效地解决常规钻井过程中经常遇到的诸如在坚硬地层中进尺慢等棘手问题,一旦得到商业化应用,将会对地热资源经济有效地开发产生革命性的影响。在分析常规钻井技术存在的问题的基础上,介绍了碎裂钻井技术的工作原理及碎岩机理,阐明了其优缺点,为该技术在地热钻井中的应用研究提供参考。 相似文献