1、华北科技学院毕业设计 外文翻译NATM tunnel design principle in the construction of major and Construction TechnologyW.BroereI.The NATM Design Principle1.Tunnel design and construction of two major theoretical and development process Since the 20th century, human space on the ground floor of the growing demand, thus
2、 the underground works of the study of a rapid development. In a large number of underground engineering practice, it is generally recognized that the tunnel and underground cavern project, the core of the problem, all up in the excavation and retaining two key processes. How excavation, it will be
3、more conducive to the stability and cavern facilitate support : For more support, Supporting how they can more effectively ensure stability and facilitate the cavern excavation. This is the tunnels and underground works two promote each other and check each others problems. Tunnels and underground c
4、averns, and focusing on the core issues with the above practice and research, in different periods, People of different theories and gradually established a system of different theories, Each system includes theory and resolve (or are studying the resolution) from the works of understanding (concept
5、), mechanics, engineering measures to the construction methods (Technology), a series of engineering problems. A theory of the 20th century the 1920s the traditional load relaxation theory. Its core content is : a stable rock self-stability, no load : unstable rock may have collapsed. need shoring s
6、tructure to be supported. Thus, the role of the supporting structure of the rock load is within a certain range may be due to relaxation and collapse of rock gravity. This is a traditional theory, and their representative is Taishaji and Principes and others. It works similar to the surface issues o
7、f the thinking is still widely used to. Another theory of the 20th century made the 1950s the modern theory of timbering or rock for the theory. Its core content is : rock stability is clearly bearing rock to their own self-stability : unstable rock loss of stability is a process, and if this proces
8、s in providing the necessary help or restrictions will still be able to enter the rock steady state. This theoretical system of representative characters Labuxiweici, Miller-Feiqieer, Fenner - Daluobo and Kashitenai others. This is a more modern theory, it is already out of the ground works to consi
9、der the ideas, and underground works closer to reality, the past 50 years has been widely accepted and applied. demonstrated broad development prospects. Can be seen from the above, the former theory more attention to the findings and the results of treatment : The latter theory is even more attenti
10、on to the process and the control of the process, right from the rock for the full utilization of capacity. Given this distinction, which both theory and methods in the process, each with different performance characteristics. NATM theory is rock for the tunnel engineering practice in the representa
11、tion method.2. NATM NATM that the new Austrian Tunneling Method short the original is in New Austrian Tunneling Method, referred to as the NATM. France said it convergence bound or some countries alleged to observe the dynamic design and construction of the basic principles. NATM concept of filibust
12、ering Xiweici Austria scholars in the 20th century, Professor age of 50. It was based on the experience of both the tunnel and rock mechanics theory, will bolt and shotcrete combination as a major means of supporting a construction method, Austria, Sweden, Italy and other countries, many practical a
13、nd theoretical study in the 1960s and patented officially named. Following this approach in Western Europe, Scandinavia, the United States and Japan and many other underground works with a very rapid development, have become modern tunnels new technologies landmark. Nearly 40 years ago, the railway
14、sector through research, design, construction combining, in many construction of the tunnel, according to their own characteristics successfully applied a new Austrian law, made more experience, have accumulated large amounts of data, This is the application stage. However, in the road sector NATM o
15、f only 50%. Currently, the New Austrian Tunneling Method almost become weak and broken rock section of a tunnel construction method, technical and economic benefits are clear. NATM the basic points can be summarized as follows : （1）. Rock tunnel structure is the main loading unit, the construction m
16、ust fully protect the rock, it minimize the disturbance to avoid excessive damage to the intensity of rock. To this end, the construction of sub-section should not block too much, excavation should be used smooth blasting, presplit blasting or mechanical tunneling.（2）. In order to give full play to
17、rock the carrying capacity should be allowed to control and rock deformation. While allowing deformation, which can be a rock bearing ring; The other hand, have to limit it, Rock is not so lax and excessive loss or greatly reduced carrying capacity. During construction should be used with rock close
18、 to, the timely building puzzle keeps strengthening Flexible support structure, such as bolting and shotcreting supporting. This adjustment will be adopted supporting structural strength, Stiffness and its participation in the work of the time (including the closure of time) to control the deformati
19、on of the rock mass. （3）. In order to improve the support structure, the mechanical properties, the construction should be closed as soon as possible, and to become a closed cylindrical structure. In addition, the tunnel shape with a round should, as far as possible, to avoid the corner of the stres
20、s concentration. （4）. Construction right through the rock and supporting the dynamic observation, measurement, and reasonable arrangements for the construction procedures, changes in the design and construction management of the day-to-day. （5）. To lay waterproof layer, or is subject to bolt corrosi
21、on, deterioration of rock properties, rheological, swelling caused by the follow-up to load, use composite lining. （6）. Lining in principle, and the early rock deformation Supporting the basic stability of the conditions under construction. rock and supporting structure into a whole, thereby improvi
22、ng the support system of security. NATM above the basic elements can be briefly summarized as : less disturbance, early spray anchor, ground measurements, closed tight.3With a spring to understand the principle NATM （1）. Cavern brink of a point A in the original excavation ago with stress (stress se
23、lf-respect and tectonic stress) in a state of equilibrium. As an elastic stiffness of the spring K, P0 under compression in a state of equilibrium. （2）. Cavern excavation, A point in attacking lose face constraints, the original stress state to be adjusted, if the intensity of rock big enough, After
24、 less stress adjustments may cavern in a stable condition (without support). But most of the geological conditions of the poor, that is, after the stress cavern adjustments, such as weak protection, we could have convergence deformation, even instability (landslides), must be provided to support pow
25、er PE, in order to prevent landslides instability. Equivalent to the Spring of deformation u, in the role of PE is now in the midst of a state of equilibrium. （3）. By the mechanical balance equation, we can see in the spring P0 role in a state of equilibrium; Spring in the event of deformation u, PE
26、 in the role they will be in equilibrium, assuming spring elasticity of K, were : P0=PE+Ku Discussion : (1) When u = 0, that is not allowed P0=PE rock deformation, is a rigid support, not economic; (2) when u , PE ; When u , PE . That is, rock deformation occurred, the release of some of the load (u
27、nloading), we should allow some extent rock deformation, to give full play to rock the capacity for self. Is an economic support measures, the rock self-stability P=P0-PE=Ku;(3) When u=umax, landslides, have relaxation load and unsafe. 4. Points（1）. Rock cavern excavation is affected by that part of
28、 rock (soil) body, the rock is a trinity : have a load bearing structure, building materials. （2）. Tunnel construction is in the rock stress is of special architectural environment, which can not be equated with the construction on the ground. （3）. Tunnel structure rock + = bracing system.II. The ne
29、w Austrian highway construction in the basic methodNATM one of the characteristics is the scene monitoring, measurement information to guide construction, through the tunnel construction measure receipts and excavation of the geological observation for prediction and feedback. And in accordance with
30、 the established benchmark for measuring the tunnel construction, excavation section steps and sequences, Supporting the initial parameters for reasonable adjustments to guarantee the safety of construction, a tunnel rock stability, the quality of the project and supporting structure of the economy
31、and so on. The author of commitments (Chengde) Chek (Chifeng) East Maojingba Tunnel NATM basic construction method for investigation concluded, synthesis of a new highway tunnel Natm the selection of different types and the basic characteristics of the construction methods and tips. 1. A tunnel cons
32、truction method of choice tunnel construction method of choice, mainly based on the engineering geological and hydrogeological conditions Construction, rock type, buried deep tunnel, the tunnel section size and length lining types, Construction should be the premise of safety and engineering quality
33、 at the core, and with the use of the tunnel function, the level of construction technology, Construction machinery and equipment, time requirements and economic feasibility of factors to consider in selection. When choosing the method for tunnel construction on the surrounding environment negativel
34、y affected, should also be a tunnel, the environmental conditions as the method to choose one of the factors, taking into rock changes the method and the applicability of the possibility of change. Tunnel project to avoid mistakes and unnecessary increase investment in public works. NATM new constru
35、ction, we should also consider the entire process of construction of auxiliary operations and changes in the surrounding rock to measure control methods and the tunnel through special geological lots of construction means for a reasonable choice. 2. New Austrian Tunneling Method program New Austrian
36、 Tunneling Method used all methods can be divided into sections, Division level and the three major types of excavation method and some changes in the program.(1) Full-face method. That whole section excavation method is based on the design of an excavation face excavation molding. Excavation order
37、is its full face excavation, steel bracing, pouring concrete lining. Often choose to IV-VI Class Rock Hard Rock Tunnel, which can be used blasting deep hole.Excavation whole section of the law is a larger space operations, introducing supporting large mechanized operations, improving the speed and p
38、rocess small, less interference and facilitate the construction organization and management. Excavation is due to shortcomings in the larger, lower relative stability of rock, and with each cycle of the relatively large workload, it requires the construction units should have a strong excavation, tr
39、ansport and slag out and support capability, Maojingba VI : Class V rock used in the full-face excavation to achieve the desired results.Full-face excavation face, drilling and blasting construction more efficient use of deep focus to accelerate the excavation blasting speed, and the rock blasting v
40、ibration frequency less conducive to a stable transfer rocks. The drawback is every deep hole blasting vibration larger. Therefore require careful drilling and blasting design and strict control of blasting operations. Full-face excavation method is the main process : the use of mobile carts (or pla
41、tforms), the first full-face a bored, and installed a line, and then drilling platform car outside 50m back to a safe place and then detonate, Blasting to make a shape out after drilling Jardine car again moved to the excavation face in place, began a cycle of drilling and blasting operations, Ancho
42、r sprayed simultaneously supporting or after the first arch wall lining.(2) step method. Step method of design is generally divided into sections on the half-section and the lower half section two excavation molding. Excavation order is its first half excavation arch bolt jet concrete bracing, arch
43、lining, the central part of the second half of excavation, sidewall of excavation, concrete wall jet bolt support and lining. The more applicable to the II, III and soft joint development of the surrounding rock, which were used Tim change program.Long-step method : The next stage distance away, on
44、the general level above 50m ahead, Construction can be assigned to the Department of next larger machine with parallel operations, when mechanical deficiencies can be used interchangeably. When the case of a short tunnel, the upper section will be all dug later, and then dug under the section, the c
45、onstruction of which less interference, single process can work.Short step method : on the stage length 5-50m apply to , rock can be shortened Invert closing time, Supporting improve early stress conditions, but larger construction interference, in the event of Soft Rock need to consider carefully,
46、Auxiliary shall be applied measures to stabilize the excavation excavation face, in order to ensure the safety of construction. Ultrashort step method : The only step ahead 3-5m, section closed faster. The method used for the high level of mechanization of various rock section, in the event of the s
47、iege soft rock when required careful consideration. Auxiliary shall be applied measures to stabilize the construction excavation face to ensure the safety of construction. Excavation level of character is the first step to using light excavation drilling machine drill a hole, rather than through lar
48、ge drilling platform car. Two step method of excavation operations with sufficient space and a faster rate of construction. Level is conducive to the stability of excavation face. Especially Excavation in the upper, lower operational safety. Three step method of excavation is the next shortcomings o
49、f operations interfere with each other. It should be noted at the bottom of the upper operational stability, level of excavation will increase the number of country rock. (3) Segment excavation method. Excavation Law Division can be divided into five changes in the program : Excavation Division level, from top to bottom hole lead, heading advance on the excavation, single (double) and lateral pit method. Excavation will be conducted Section Division excavation by the Ministry of sha
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