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71.
For existing advanced geological forecasting, the forecast distance is short and the test frequency is high, increasing test and construction risks. Since various methods have different requirements for the test environ-ment, preparation work can be tedious and result in a long construction time thereby affecting normal construction.A new advanced geological forecast technique based on multi-source seismic interferometry for tunnels is proposed.This technique uses the blast at one end of tunnel as a centrum and receives the signal at the other end of the tun-nel, therefore allowing advanced geological forecasting of the unexcavated tunnel part by relative processing and im-aging. A numerical simulation of this kind of geological forecasting using the finite difference method to simulate two kinds of unfavorable geological bodies (karst and a fault) predicted them accurately and verified the effective-ness and accuracy of this geological forecasting method. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
72.
Defects of tunnel lining, such as inadequate thickness, voids, cracks, rock falling and water leakage etc., endanger the safety of railway tunnel operation. Based on the site construction, an analysis of the reasons for lining defects was conducted; technical measures against lining defects were proposed and tests were carried out at site. The results show that these measures are reliable and effective, and the purposes of prevention and treatment are re⁃ alized. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
73.
Sofia Grahn-Voorneveld 《Transportation Research Part A: Policy and Practice》2012,46(4):645-651
Usually transport systems, and roads in particular, are viewed as public goods. However, this is not always the case. In Sweden a large part of the road system is privately owned. Most of these privately owned roads are rural roads used by farmers and summer cottage owners, or used for forest transport. These roads are mainly provided by ownership associations.An important difference between public roads and these privately owned roads is that all investments- and maintenance decisions are made by the users themselves, who also have to pay the costs, whereas the usual case is that the owners/providers of a road-system are different agents than the users. Here the question is not how to charge the roads but how to split the costs of the roads among the users in an efficient and “fair” way.The motivation of this paper is the practical problem of how such an ownership association can divide the costs for the road network among the members in an efficient and “fair” way. The problem is treated from a game theoretical point of view, making use of the Shapley value. This means that the problem is associated with a game - a mathematical representation of the conflict situation. The Shapley value is a very important solution concept for cooperative games, like the game in this case. For games corresponding to this specific type of problems, it is shown that the Shapley value has excellent properties, such as beeing an element of the core, and beeing very easy to compute. 相似文献
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文章采川三维有限元数值模拟研究了偏压连拱隧道不同施工顺序下拱顶下沉、中墙稳定性及初期支护受力特征.研究结果表明,先开挖浅埋侧时,拱顶沉降较小,中墙在施工中的稳定安全系数较大、弯矩较小,初期支护受力较大;对于浅埋偏压连拱隧道,围岩变形及中墙在施工中的稳定性控制更为重要.所以,从有利于围岩变形、中墙稳定性控制以及中墙受力的角度出发,宜采用先开挖浅埋侧的施工方法. 相似文献
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文章对岜肯隧道浅埋偏压段洞口施工中出现的塌方及初衬开裂情况进行客观分析,结合施工实际提出了地表加固及平衡土体偏压措施,有效地控制了地表变形及隧道沉降开裂,保证了隧道施工安全、顺利进行。 相似文献
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西部地区公路地质灾害监测预报技术研究 总被引:1,自引:0,他引:1
贵州省交通规划勘察设计研究院 《西部交通科技》2009,(3):42-46
“西部地区公路地质灾害监测预报技术研究”项目针对西部地区公路地质灾害危险性区划、滑坡、崩塌与泥石流监测预报及地质灾害安全管理等关键技术问题进行深入系统研究,形成了公路滑坡、崩塌与泥石流监测预报成套技术,建立了公路地质灾害数据标准,构建了“基于GIS的公路地质灾害监测预报信息系统”平台,实现了公路地质灾害监测实时分析处理和动态预报,为地质灾害综合管理提供技术支撑。 相似文献
79.
浅谈筑路机械设备管理 总被引:1,自引:0,他引:1
文章通过分析筑路机械设备管理的背景和意义,针对目前筑路机械设备管理存在的问题,提出了相关对策,为公路施工企业提高筑路机械设备管理水平提供借鉴。 相似文献
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