地铁施工工法比较 英文

1、 Chapter3 Program comparison3.1 summary With the acceleration of the process of China's rapid economic development and urbanization, the existing road transport system has not meet the travel needs of the people.To ease the ever-increasing traffic pressure, China's major cities to speed up t

2、he construction of urban rail transit systempace. Comparative Analysis of rail transit and several other common way to travel, the rapid rail owns transit efficiency, energy saving, environmental protection, large volume, high speed, low pollution, low noise, low power, small footprint, safety, comf

3、ort, all-weather, etc.a unique advantage to solve urban traffic congestion, changing the urban layout. It has played a big role to achieve comprehensive management of urban environment and transport, and guide the city and take the road of sustainable development.However, the tall buildings of the u

4、rban area-intensive, crowded, traffic, bus lines, subway station design is becoming increasingly narrow construction of space, around pipeline dense, close to existing buildings, ground with heavy traffic and many other constraints.3.2 Several commonly used methods of subway station constructionSubw

5、ay stations located in the city center, mostly, therefore,the selection of construction methods and structure type of subway station , mainly based on the following aspects: (1)station function, station function mainly reflect from the station use effect and operation conditions, and the station use

6、 effect reflect from the capacity of the organization and distribution in passenger, equipment room decorate, operation management and utilization of underground space in comprehensive functions; (2) difficulty of construction, mainly from the difficulty of construction project itself, construction

7、preparation of the implementation of the degree of difficulty, period and construction safety aspects of evaluation, embodied at the the maturity of construction technology and surface subsidence control, construct objects demolition, pipeline move and protection; (3) environmental impact of constru

8、ction, environmental impact on the construction mainly embodied in the influence of urban traffic and urban living, the influence of the commercial activities, and pollution to the environment, etc. Subway station construction method has a lot kinds, commonly used in China are now open cut method, c

9、ut-and-cover method, cover excavation method and hybrid method,etc. Which cut-and-cover method consists of the bottom up and top down; open cut methodOpen-cut method is the traditional construction method of the ground frame structure.First of all, make the foundation pit on the ground, and then exc

10、ave the soil from top to bottom, plus support when necessary to prevent the deformation of foundation pit,when excavation in the end facilities for the framework from the bottom up.The construction technique of open-cut method is simple, rapid, and economy, so the subway station construction regarde

11、d open-cut method as the preferred solution. Construction of the open-cut method generally are used to cut-bottom up, cut-bottom up construction method in the construction sequence is as follows.Fig A.1 Open-cut excavation procedure cut-and-cover methodCover and cut-bottom up method after completion

12、 of the retaining structure, the cover to the stereotypes of prefabricated standard structure (including the longitudinal beams and pavement slab) placed in a retaining structure to maintain traffic, be down repeated excavation and set up cross-hold until the design elevation. Fig A.2 cut-and-cover

13、method-bottom up method procedurecover and cut-top down method steps: first to the ground surface down to do the pit of the envelope and intermediate piles the same with cover and cut-bottom up method, the foundation pit structure use of underground continuous wall or curtain pile.The intermediate s

14、upport is more of the middle column of the main structure itself in order to reduce the project cost.Fig A.3 cut-and-cover method-up dowen method procedure Shallow depth of cover excavation methodIn urban centers, ground transportation do not allow long-term interruption because of many buildings on

15、 the surface, a small ground construction site , the impact of a number of bridge pile in the city under the overpass, or pipeline complex,so its difficult to change the shift. So when the geological conditions allowed,its considered the tunneling method to subway station facilities(1) the CD method

16、.Fig A.4 the CD method procedure(2) the CRD methodFig A.5 the CRD method procedure(3) the double benching tunneling methodFig A.6 the double benching tunneling method procedure(4)the middle hole methodFig A.7 the middle hole method procedure(5) the lateral hole methodFig A.8 the lateral hole method

17、rocedure (6)the PBA methodFig A.9 the PBA method procedure3.3 Comparison of the subway station construction methodTable A.1 The mainly construction method of subway stationConstruction MethodApplicable ConditionsAdvantageDisadvantageOpen-cut methodOpen pit or building in which widely spaced ground,

18、the ground has enough open space to meet the construction needsLow cost, Mature skill, Safe construction, Short duration, Facilitate to operate with large machineInterrupt the ground traffic, Easy to Damage the environmentCover excavation methodThe ground traffic can not be interrupted and has to en

19、sure certain traffic requirementMature skill, Rational structure, Little occupied time, Little disturbance of the ground trafficHorizontal construction joints of concrete structures is difficult to treat; the excavation is difficult and high costMining methodCan be used under any conditions in case of reasonable supportAvoid a large number of shift work, the construction process is simple and flexible, no need of large-scale equipment, Be particularly suitable for variable cross-section, construction wont interrupt the ground trafficHigh construction