共查询到19条相似文献,搜索用时 109 毫秒
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介绍了浮球式海底取样器的结构,性能特点,典型应用及性能参数;论述了振动式振动冲击式贯入理论的原理;并分析了海流及船体飘移对海上取样作业的影响及解决办法。 相似文献
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天然气水合物是一种潜力巨大的替代性能源,其可以稳定地存在于一定的低温高压条件之下。在天然气水合物钻探作业中,冷却保温技术是天然气水合物钻探的关键技术之一。低温可以抑制天然气水合物分解,这对获取水合物样品有着十分重要的作用。本文首先概述了海底天然气水合物取样器保温冷却技术研究现状,并对取样器冷却保温技术进行深入的调查研究和分析。然后对日本的PTCS取样器中的冷却保温技术和国内具有冷却保温功能的取样器进行了详细介绍,并对相关技术进行分析和总结,最后对海底天然气水合物取样器冷却保温技术的发展做了总结与展望。 相似文献
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Ascertaining the minimum rock covers of subsea tunnel is important to reduce project cost on the conditions of subsea tunnel safety. Researching the dynamic influence of tunnel blasting construction on the cover rock mass is necessary to the minimum rock covers. The effect of subsea tunnel construction using drilling and blasting method to overlaying strata is analyzed through FLAC3D numerical simulation. The influence of different subsea tunnel level and charge weight on the interface of overlaying strata is analyzed. The blasting vibration velocity history and stress vibration history at key points and the plastic zone are gained and contrasted with the result of experimental formula; synthesizing the above analysis and considering economical and safety of subsea tunnel, we suggest that charge weight should be reduced and subsea tunnel level should be descended 2 meters. 相似文献
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The subsea tunnels all over the world are investigated; and the three methods, such as Norway experiential method, the minimum leakage method and coal cutting experience under water, are summarized. According to above-motioned methods, the engineering analogy is used to decide the minimum rock cover of a subsea tunnel at Xiangshan Harbor. The results of three methods are thought over overall. Meanwhile its geology is considered. Then the optimal rock cover is gained. To take into account the subsea landform and geology, a profile is chosen to be the reference profile. According to the design gradient of the subsea, the tunnel motherboards and the rock covers of profiles are obtained. Comparing those with the results of engineering analogy, the shortcut of tunnel is got under the safety condition by adjusting the gradient of the part of the tunnel motherboards; so the optimal scheme to construct the subsea road tunnel is decided. 相似文献
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Prof. Dr. B. Nilsen 《Rock Mechanics and Rock Engineering》1994,27(2):63-75
Summary As a part of a research program on the rock engineering aspects of hard rock subsea tunnelling, analyses of potential cave-in from fault zones have been carried out at the Norwegian Institute of Technology. This is a topic of great importance for the planning of future subsea tunnels, and particularly for the selection of the minimum rock cover of such projects. The paper is divided into three main parts: a) review of cases of instability in Norwegian subsea tunnels, b) evaluation of theoretical maximum sliding, and c) discussion of cases of cave-in in tunnels under land. In theory, a cave-in during subsea tunnelling may propagate far higher than the normal minimum rock cover. Taking into consideration the comprehensive geo-investigations that are always carried out for subsea tunnel projects today, it would, however, be unrealistic to base the dimensioning of rock cover for future projects on worst-case scenarios. Consequently, the main result of this study is to emphasize the importance of comprehensive geo-investigations, detailed tunnel mapping, a high degree of readiness during tunnelling and a thorough quality control. 相似文献
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The rock cover depth of subsea tunnel is a key factor to the tunnel stability as well as economy and should be evaluated carefully. At present, there is no a standard in how to select it. Based on the characters of rock cover depth selection, according to the experience of subsea tunnels which have been built, empirical analogue methods have been carried to research it. Through employed empirical analogue methods into an actual engineering, reasonable rock cover depth ranges can be obtained. The methods proposed can provide reference for the design of other subsea tunnels. 相似文献
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厦门翔安隧道是国内修建的第一条海底隧道,其相关勘察、设计以及施工经验和工程总结材料将对国内其他海底隧道的建设具有十分重要的借鉴作用。与山岭隧道相比,需要解决的岩体力学与隧道工程结构设计等方面的问题不尽相同,存在不少现行规范未能涵盖而又亟待在设计中予以明确回答的问题。根据厦门翔安海底隧道风化槽强风化花岗岩的室内应力-渗流耦合试验成果,建立了强风化花岗岩的应变硬化的弹塑性模型和黏聚力演化方程,通过反演确定了模型的力学参数。研究表明,提出的应变硬化的弹塑性模型能合理地反映强风化花岗岩的力学特性,其成果具有很好的推广应用价值。 相似文献