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931.
Dong Y.-P.Sun B.-L. 《铁道工程学报》2018,(11):87-91
Research purposes: At present, the urban subway is developing rapidly in our country, among which there are many problems. This paper takes a seven-story frame structure office building as research object. In view of the phenomenon that the dome subsidence and the land subsidence rate exceed the early warning in the field construction of the left line tunnel, combing theoretical analysis with the MIDAS-GTS numerical simulation, we took the "building-stratum-tunnel" as the research object, analyzed the influence of small distance tunnel construction process of mine method on the adjacent buildings, and analyzed the influence difference of the construction sequence of the left and right lines. Finally we put forward the relevant engineering technical measures. Research conclusions:(1) The tunnel construction makes the building in the tensile zone, and the structure is easy to be damaged. When the structure is far away from the influence of the excavation, the order of tunnel excavation is not significant. (2) When the surrounding rock is broken and close to the building, it is better to excavate the tunnel far away from the side of the building. At the same time, we should pay attention to taking the reinforcement measures near the side of the building and the intermediate rock column. (3) The research results can be applied to the field of shield construction in subway, and have a good guiding effect on the shield tunnel passing through buildings at close distance. © 2018, Editorial Department of Journal of Railway Engineering Society. All right reserved. 相似文献
932.
《铁道标准设计通讯》2017,(4):126-131
为探究小净距隧道群洞穿越不同地层施工引起的力学响应,基于青岛地区土岩复合地层特殊地质条件,通过数值计算并结合现场测试数据,分析小净距地铁隧道群洞施工引起的地表沉降、应力特征、拱顶变形规律。结合工程实际,将隧道群洞施工划分为4个不同阶段并依此分析,结果表明:隧道群在其阶段Ⅳ施工后引起地表沉降变形较大,其他阶段地表沉降无明显变化;不同开挖阶段对夹岩的扰动程度存在差异,阶段Ⅳ施工使夹岩主应力出现剧烈变化,且夹岩最薄弱处最不利状态发生于阶段Ⅳ,但无剪切破坏现象;隧道拱顶沉降最大增量在该条隧道开挖后出现,上线隧道施工显著影响其他隧道拱顶沉降,且能够引起中线隧道拱顶抬升。研究成果为同类工程的施工稳定性分析提供了现场指导和技术支持。 相似文献
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937.
The objective of the work was to evaluate the potential user response to distance and time based road pricing of a sample
of individuals drawn randomly from a group of volunteers in Dublin. The road use pricing charge levels were selected to match
the marginal external costs of car transport i.e. those costs not currently paid by the car user. Such costs include marginal
external costs of congestion, air pollution and noise. The project formed part of the EU DGXVII EUROPRICE project where one
of the objectives was to evaluate the impact of road use pricing on private transport demand. Estimates of the marginal external
costs of car travel had been previously made for Dublin in an EU DGVII project entitled TRENEN II STRAN and the results were
used to select the road pricing charges in the trial. The distance travelled and travel time of a particular individual's
work trip were noted. Charges per unit distance and time were applied so that the individual would incur a total charge for
their average peak period work trip of 6.4 euro; the average marginal external cost of a peak period trip in Dublin, as estimated
by the TRENEN model. Although the sample of individuals was relatively small, the indications from the results are worthy
of note and further investigation on a larger sample. A significant reduction in the number of peak period trips was evident,
of the order of 22%, resulting from trip suppression and transfer to other modes.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
938.
扼要叙述了LKJ-93型列车运动监控记录装置测距系统找硒原理,基本构成、测距工作的必要性、测距的主要内容、重点阐述了测距主机软件的设计思想,提出了新颖的“双轮径方案”。 相似文献
939.
分析了越江区间内列车按移动闭塞方式行车的区间最小追踪间隔。探讨了在移动闭塞系统下风井设置与列车最小追踪间隔的关系,根据实际工程牵引计算进行校验。 相似文献
940.
在既有以人控为主的管理机制下,由于地铁车辆基地内检修库、运用库为半开放式区域,人员进出和列车出入库较为频繁,故存在人车冲突的安全隐患。通过对车辆基地检修库、运用库的股道列位设置以及列车运用场景进行分析,提出一种基于激光的车辆基地列车动车预警系统设计方案。该系统以激光测距技术为基础,测量出列车运动过程中的不同距离信息,通过计算机技术的逻辑处理后,分析出列车的不同运动情形,实现列车动车的自动预警。目前已在上海地铁12号线金桥车辆基地试点应用,试点结果表明,该设计方案合理可行,一定程度上降低了作业人员人车冲突的安全风险。 相似文献