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1.
美国五种运输方式(包括城市交通)统一由联邦运输部综合管理。公路运输由运输部下设的公路署管理,道路运输行政管理属于整个运输行政管理系统中的一部分。一、联邦运输部机构设置及其管理责权1、联邦运输部机构设置美国联邦运输部成立于1967年,目前其下设管理机构如图1所示。2、联邦运输部管理责权①联邦运输部部长责权美国法典49(运输法典)“301领导、协商和协调”条款中规定,运输部长具有如下责权:·在总统指导下领导运输事务,包括影响国防和涉及国家及地区紧急情况事务;·领导制定运输政策和开发项目,向总统和国会提出有关政策及其实施建…  相似文献   

2.
The strata of Chengershan tunnel is mainly consist of the slightly cemented tertiary sandstone, the tun⁃ nel body passes through F 2 fault core zone. Geological disasters of mud outburst, sand gushing and extrusion of work face occurred several times during tunnel construction, so the risks are very high. In view of the core zone of F 2 fault with high pressure and abundant water, a variety of construction schemes were compared and analyzed in terms of technology, feasibility and safety, and vertical freezing technique was used for stratum reinforcement in the railway tunnel for the first time, furthermore the freezing scheme and tunnel support measures were studied, providing refer⁃ ence and guidance for similar tunnel construction.Mountain railway tunnel; Fault zone; Tertiary sandstone; Vertical freezing technique; Application © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

3.
The Olympic Park Station crossing the existing Datun-Road tunnel covers a long distance and closely approaches an existing metro tunnel. Initially, the PBA construction method was adopted with eight pilot tunnels. In light of the tunnel group cavern effect and the surrounding soft silty clay with abundant water, the construction risks were very. Optimization of the metro station construction scheme was conducted, and the four pilot tunnels at the downside were cancelled and replaced with long drill hole grouting piles. Construction technology for a large-diame-ter pile for a bored pilot tunnel was adopted based on the engineering characters of the PBA method using four pilot tunnels. Monitoring on the Datunlu tunnel structure was performed during metro station construction and the results indicate that the construction scheme for the station’s main structure was rational; the new construction technology ensures construction safety for the existing tunnel and metro structure. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

4.
Improvements of management mode and application level of informationization techniques are the key factors to safe and efficient construction of the high-speed railway tunnels considering the complexity and diversity of construction techniques, unpredictable risk factors and varied geological conditions. In the paper it proposed a management mode for lean construction of high-speed railway tunnels, studied the in-depth integration and applica⁃ tion of key technologies of BIM, advance geological prediction, tunnel surrounding rock measurement, 3D laser scan⁃ ning, etc. in the lean construction management of high-speed railway tunnels, and developed the light portal APP and cloud-based information management system. Through the verification of practical engineering application, it re⁃ alized good monitoring of key risk resources in tunnel construction, redline control for key tasks and effective manage⁃ ment of safety and quality, increased efficiency of collaborative operation of all parties involved and reached the goal of lean construction and management. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

5.
9月15日,上海合作组织成员国第五次总理会议在塔吉克斯坦首都杜尚别召开,交通部副部长冯正霖代表中国交通部与俄罗斯运输部、哈萨克斯坦运输通信部、吉尔吉斯斯坦运输通信部、塔吉克斯坦运输部、乌兹别克斯坦对外经济联系投资贸易部签署了<关于加快制订〈上海合作组织成员国政府间国际道路运输便利化协定〉(草案)的谅解备忘录>.温家宝总理出席了签字仪式.  相似文献   

6.
The evaluation of the stability of a tunnel’s primary support is a crucial component of ensuring the safety of subsequent construction. In light of the measured clearance displacements of the Wushishan Tunnel, the reliabili-ty of the primary support is evaluated dynamically and the design of the support structure is optimized. The research results show that full displacement and ultimate displacement are two main parameters for tunnel reliability analy-sis: the former can be obtained by positive and negative analysis, and the latter can be acquired by simulating a field measurement of displacement. It is not sufficient to apply the data specified in the code for railway tunnel design re-liability regarding determination of the reliability of a road tunnel structure using reliability theory, and it is neces-sary to use reliability theory to amend the standard of allowable empirical displacement in the Code of Road Tunnel Design. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

7.
本文主要分析美国联邦运输部、运输部所属机构及州运输部运输战略规划的主要内容及特点。分析美国各层次运输战略规划对我国当前运输发展规划的制定具有借鉴及启示作用。  相似文献   

8.
Zhang M.  Zhang Z.  Chen F. 《现代隧道技术》2018,(6):197-203and209
A variety of construction problems, such as bad cutting effects of cutters, unreasonable boring parame- ters and blowout, are often encountered during shield tunnelling under unfavorable geological conditions. Aimed at these construction difficulties of high pressure, abundant underground water, fractured rock stratum, long distance and small-radius curves of Fuzhou metro, the mechanical behaviors of cutting tools were analyzed through theoreti- cal calculations of cutter cutting force, then the reasonable cutter configuration, tunneling parameters and the proper time for cutter replacement were presented. Some measures, such as screw conveyor renovation, mucking control and lowering of groundwater, were adopted for controlling blowout based on practice. The stability of excavation face was analyzed by numerical simulation, and the measures for shield boring and posture control in the long distance and small radius curved tunnels were summarized. The conclusions are as follows: 1) when shield machine is driven in fractured stratum, the effect of lateral impact force produced by spalling rock on cutter will be very large and rein- forcement is needed for cutter; 2) cutter replacement should be taken at proper time based on muck samples in con- ditions of increasing of total shield thrust by 4 000-7 000 kN, cutter torque by 1 000-1 500 kN•m and driving speed smaller than 10 mm/min; 3) adopting screw conveyor device with innovative anti-blowout devices and control measures for ground precipitation and mucking, it controls blowout effectively; 4) the maximum axis offset and the height offset of segment meet the requirements of shield construction specifications during shield construction of long distance small-radius curved tunnel. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

9.
《文通节能与环保》从2013年起变更为双月刊。该杂志是由中华人民共和国文通运输部主管,文通运输部长江口航道管理局和交通运输部公路科学研究院共同主办的国家级科技期刊。全国统一刊号:CN31-1355/U,国际标准刊号:ISSN1673-6478。《文通节能与环保》以报道中国文通领域节能减排的新技术和科技创新成果为宗旨,依托交通  相似文献   

10.
Jacking force is the most important parameter in jacking pipe engineering, and reasonable calculation of jacking forces plays an important role in safe and smooth pipe jacking construction. There are many calculation methods for pipe jacking force at present, and the calculation results may be affected to some extent by different cal⁃ culation methods. For this reason, calculation methods of jacking force (frictional resistance) were collected and a comparative analysis was conducted with aspects to the advantages, disadvantages and applicabilities. The results show that as for the jacking force calculated by empirical formulae, the soil layer classifications corresponding to giv⁃ en frictional force per unit area and relevant factors to be considered are different, and the values of frictional force per unit area between pipe and soil in the same soil layer are also different; as for the jacking force calculated by theo⁃ retical formulae, the calculation methods for vertical earth pressure at crown are different and much effected by the pipe buried depth; as for the jacking force calculated by numerical simulation, the selected theories for the simula⁃ tion program and the construction factors to be considered during simulation are different. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

11.
Based on the blasting construction of a Qingdao metro tunnel, a linear regression analysis of Sodev’s em-pirical formula mentioned in the GB6722-2014 Safety Regulations for Blasting is conducted considering the geologi-cal conditions of Qingdao and collected blasting vibration monitoring data. An empirical formula to predict the am-plitude of the vibration intensity of Qingdao metro tunnel blasting is deduced, while the allowed vibration velocity,single-hole charging load and scope affected by the construction vibration are determined. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

12.
<正> 中国—加拿大综合运输管理培训项目第四期高级管理人员培训班于1996年6月1~27日赴加拿大进行实地考察学习。在加期间分别考察了温哥华、维多利亚、多伦多、渥太华和蒙特利尔等城市的综合运输情况,走访了BC省运输部、安省运输部、国家运输部、国家运输署、国家财政委员会和运输发展中心等政府部门及研究机构,参观了一批公路、铁路、机场和港口企业及运输设施。通过4周的学习,对加拿大交通运输的现状、特点及走势有了一定的了解,特别是近几年的运输企业体制改革给我们留下了深刻的印象,得到了许多启示,对今后的工作将有很大的帮助。现整理总结如下:  相似文献   

13.
In a perspective of modern tunnelling philosophy, some problems on conventional tunnelling in soft rock mass were discussed. The development process of rock mechanical behavior and deformation caused by excava⁃ tion is attributed to the change course from yielding to discrete. Some effective control means were presented as well and the effect of advanced support system was evaluated. As to the deformation controlling technology for squeezing ground, the theory and design principle of yielding support system were introduced. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

14.
The new Badaling tunnel is the longest tunnel on the under-construction Beijing-Zhangjiakou highspeedrailway, with the Badaling Great Wall station to be built in the tunnel. This station, which is under the Badaling Great Wall historic site, is the world’s largest underground high-speed railway station with the most complicated structure and the largest overburden and excavation area. It is therefore a representative project for China’s highspeed railway development strategy, supporting infrastructure facilities for the Beijing Horticultural Expo 2019 and the 2022 Winter Olympics in Beijing, and it is important that it be of high quality and completed safely. In the de-sign and construction of the station, the glyphs of the Chinese characters of "中",”国”,”人”and”品”are used, re-spectively, along the station route, in the rescue and evacuation mode, auxiliary adit and partial excavation, which is a way to successfully integrate the art of Chinese characters into tunnel engineering. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

15.
Light distribution (LD) and installation style of luminaires affect the utilization factor (UF) of luminaires, and the UF affects the luminaire power and road pavement illuminance and further the power consumption of illu- minating system and the luminous effect of road pavement. An UF model of tunnel lighting was established based on the luminaire LD data and installation parameters, in which four LD styles were adopted. For each LD the parame- ters optimization and simulation were conducted regarding four installation styles, e.g. central style, offset-of-vault style, symmetric style and staggered style. The energy-saving and the lighting effects of each LD and luminaire in- stallation style at the tunnel middle zone were studied. The results show that symmetric luminaire installation is the most energy-saving style and has the best lighting effect than the other three luminaire installation styles; the lighting effect of central luminaire installation is the second best; staggered luminaire installation is the most energy-intensive style and has the worst lighting effect except for some special-shaped LD; waterdrop-shaped LD is the most suitable one along transverse direction of tunnel and applicable to the central, offset-of-vault and symmetric luminaire instal- lation styles; symmetric butterfly-shaped LD is the most suitable one along longitudinal direction of tunnel and appli- cable to the central, offset-of-vault, staggered and symmetric luminaire installation styles; with waterdrop-shaped LD along transverse direction and symmetric butterfly-shaped LD along longitudinal direction, they are suitable for the above four luminaire installation styles, and have better energy-saving and lighting effect; as for the LD with symmetric and oblique curve, it’s better for the profile of oblique luminaire distribution to be comply with that along tunnel transverse direction, and it is suitable for the symmetric and offset-of-vault luminaire installation styles. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

16.
Gong C.  Luo Y.  Zhang J. 《现代隧道技术》2018,(6):210-216and221
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   

17.
It's really challenging for shield driving when hard rock partially intrudes into the excavation section of metro tunnels. Abnormal cutter wear is excessive during shield excavation in hard rock and comprehensive perfor⁃ mance of excavation system decreases greatly, resulting in abnormal advancing parameter, small penetration rate and low advance rate. Taking Shenzhen Metro line 9 project as the background, the main difficulties encountered for the compound EPB shield during driving in high-strength granite and the reasons were analyzed, the corresponding countermeasures were presented. EPB shield drove through the hard rock section safely and smoothly attributed to reasonable cutter configuration, in-time cutter replacement and proper advancing parameters. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

18.
Based on an introduction to the construction and application of the early warning control platform for the tunnel and subway engineering, an overall analysis of the related data during tunnel and subway construction was conducted in order to give a better reference for the site construction, to guarantee safe and rapid qualified construc⁃tion, and to improve management efficiency. Based on red line control, deformation thresholds of surrounding rock, allowances of construction material and advanced geological prediction, a dual early warning system with automatic trigging and manual prejudging was adopted to control the quality of tunnels and subways and to guarantee safe con⁃ struction; through the platform a centralized management is realized, all the construction information and effective data are transmitted instantaneously by internet, decreasing management cost and increasing work efficiency. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

19.
The earth pressure acting on a shield tunnel is intrinsically related to synchronous grouting, the position of the shield machines, the rigidity of the segment and stratum, etc. Existing theoretical formulas and empirical methods couldn′t exactly reflect the actual state of the segment of a shield tunnel during construction due to the com⁃plexities mentioned above. Based on earth pressure data measured at 52 monitoring sections in 35 tunnels, the distri⁃bution laws and influential factors are analyzed. The results show that: 1) the earth pressure scope is 0 to 400 kPa for over 90% of the total samples, but is recommended to be 0.3 to 0.4 MPa for the empirical grouting pressure; 2)the earth pressure on the segment and the buried depth approximately have an exponential relationship, with the dif⁃ference between the max. earth pressure and the stable earth pressure decreasing with an increase of the buried depth; 3) the lateral pressure coefficient range is 0.5 to 2.3, which is partially out of the scope of recommended values(0.5 to 1.0) of surrounding rock of grade Ⅵ, so it is not appropriate to follow the recommended values in the specifi⁃cation; 4) the relationship of the earth pressure and the segment/soil stiffness ratio presents a quadratic function, and the most reasonable value for the stiffness ratio of the segment/soil is 1.0; and 5) there are four typical stages of the spatial distribution of earth pressure on a segment in clay stratum—the erection stage, the grouting influence stage,the consolidation contraction stage and the recovery stage, with the distribution of the circumferential earth pressure being asymmetrical. The distribution curves of the earth and water pressure in sand and soil layers are classified as a“weak decay pulse fluctuation”and“double hump,”respectively. After stabilizing, the circumferential earth pressure is notably in a symmetrical distribution, and the water pressure exhibits a light bulb shaped distribution (large at the lower part and small at the upper part). These conclusions provide a reference for studying the mechanism of earth pressure functions and perfecting the design of segments for shield tunnelling. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

20.
正德国道路货物运输行政管理体制德国联邦交通与数字基础设施部(以下简称"德国联邦交通部")内设陆路运输司(Land Transport),陆路运输司下辖的道路交通运输局具体负责德国道路交通运输行政管理事务。道路交通运输局在联邦货运管理局、联邦车辆局、联邦公路科学研究所等协助下,主要负责诸如驾驶执照的获取、道路使用者行为、经营性客运或货运车辆的技术要求及注册等事项。德国是一个联邦制国家,在联邦制基础上实行地方自治,德国的国家行政一直由联邦政府行政与地方(州、市/县)行政所组成。在交通  相似文献   

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