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991.
杭州铁路东站西广场地下室为2层的超大开发空间,位于已竣工的地铁区间盾构隧道的上方,影响范围约358 m,二者之间的垂直净距约6.73 m。为评价西广场地下空间约10 m深的基坑开挖施工工艺对地铁盾构隧道的影响,从而选择合理的基坑开挖方式,通过采用FLAC 3D大型岩土分析软件,模拟西广场基坑开挖分层分块施工工艺对地铁隧道的变形及受力性能的影响,得出分层分块开挖对下方盾构隧道不会造成破坏的结论,并提出地铁隧道的监控要求,监测结果表明分层分块基坑开挖工艺满足地铁隧道安全运营要求。 相似文献
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张朝霞 《铁道标准设计通讯》2018,(3):58-61
南三龙铁路合福联络线闽江特大桥主桥为(118+216+118)m预应力混凝土连续刚构,为国内已建和在建项目中主跨最大的高等级铁路连续刚构桥。随着预应力混凝土刚构跨度增大,桥梁的刚度以及混凝土的后期徐变控制成为设计难点。从方案比选到主梁设计,介绍本桥的设计思路以及体外索的设置等关键技术,并研究3种车型通过桥梁时车桥耦合动力效应。结果表明:本桥各项指标均满足规范要求,并留有适当的安全储备,具有良好的动力特性,列车通过桥梁时安全性和乘坐舒适性均满足要求。 相似文献
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We propose a new type of timetable that would combine both the regularity of the cyclic timetables and the flexibility of the non-cyclic ones. In order to do so, several combinations of the two timetables are considered. The regularity is incorporated in their design and the flexibility is evaluated using the passenger satisfaction (in monetary units). Each of the tested timetables is constructed using the Passenger Centric Train Timetabling Problem (PCTTP), that is solved using a simulated annealing heuristic. Note that the PCTTP, unlike the traditional Train Timetabling Problem (TTP), does not take into account the conflicts among trains. The aim of the PCTTP is to design such timetables that the passengers’ satisfaction is maximized and it remains the aim of the TTP to remove any potential conflicts. The performance of each of the considered timetables is assessed on the real network of Israeli Railways. The results of the case study show that our proposed hybrid cyclic timetable can provide the benefits of the cyclic and the non-cyclic timetable simultaneously. This timetable consists of 75% of cyclic trains (securing the regularity of the service) and of 25% of non-cyclic trains (deployed as supplementary trains during the peak hours and capturing the demand fluctuation). The level of the passenger satisfaction of the hybrid cyclic timetable is similar to the level of the non-cyclic one, which has about 18.5% of improvement as compared to the purely cyclic one. 相似文献
994.
Surface soil (0–10 cm) samples from 60 sampling sites along the length of railway tracks on the territory of Srem (the western part of the Autonomous Province of Vojvodina, itself part of Serbia) were collected and analyzed for seven polychlorinated biphenyls (PCBs) and ten heavy metals in order to see how the distance from the railroad affects the concentration of some organic and inorganic pollutants in the soil. Samples were taken at a distance of 0.03–4.19 km from the railway. For the soil extraction was used USEPA 3540S method. The extracts were purified on a silica-gel column (USEPA 3630C). The analysis of the extracts was performed by gas chromatography with tandem mass spectrometry. PCBs were not detected only at two locations. Mean total concentration of PCBs for all other sampling locations was 0.0043 ppm dry weight (dw) with a range of 0.0005–0.0227 ppm dw. According to values of Nemerow pollution index Cu, Co, Zn and Ni were the most ubiquitous heavy metals in the area near railroad. Based on these results, it can be said that railway transport is a potential source of PCBs and some heavy metals. 相似文献
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针对铁路改革的严峻形势,分析了当前基层站段生产管理经营面临的难题,从建新机制,强基础管理的角度,提出了解决生产成本控制,提高生产经营管理水平的基本方法。 相似文献
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《铁道标准设计通讯》2017,(7):19-22
鉴于目前如数字高程模型(DEM)、高清网络地图等各种高新前沿技术在铁路线路设计中的应用,迫切需要线路辅助设计软件与时俱进引入相关技术,通过对相关高新前沿技术的深入研究成功开发了相关软件,软件应用了许多高新前沿技术,很好地解决了线路设计及软件开发中的难点问题,经实践证明本软件具有技术先进、使用高效的优点。 相似文献