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1.
In order to deal with the technical problems of Shuangfeng Tunnel passing through water rich Tertiary sandy mudstone strata with long distance and big overburden, such as dewatering, advance reinforcement, structural design and construction method etc., reducing tunnel deformation, preventing water inrush, gushing mud and tunnel collapse, the technical route of "stereo exploration, pressure reduction by water releasing, pre grouting, supporting timely, overall monitoring" is established after the field test and data analysis. Methods of full dimensional exploration and water pressure reducing are proposed, which form the preceding reinforcing technology that are different between inside the excavation contour and outside the excavation contour. Support linings are constructed immediately after excavation of upper bench. Safety performance of tunnel structure is evaluated according to the monitoring results. The research is conducted based on Shuangfeng Tunnel and the study results are applied in the construction of the tunnel. Results indicate that it can make sense to control deformation and ensure safety by using methods of reducing pressure through full dimensional water release, adopting advance reinforcement measures that are different between inside the excavation contour and outside the excavation contour, proposing mini bench method during tunnel construction and supporting timely after excavation for tunnels passing through water rich Tertiary sandy mudstone strata.  相似文献   

2.
Confronted with accidents in a shallow?buried weak tunnel using the bench excavation method,such as great subsidence and cracks in the ground surface as well as those in the preliminary support,a double downside drifts construction method was presented The drifts were used to detect geological conditions and reinforce the lower parts of the tunnel Its construction procedures and load transiting mechanism were then described Its Construction behavior was also studied by numerical simulation using software MIDAS The results show that (1) double-side drifts can improve tunnel load,the key construction step is arch ring excavation and core soil is good to keep tunnel steady; (2) weak parts mainly l ocate at wall foot of drifts,wall foot and crown foot of tunnel,and the connections; (3) reinforcement of soil under the drifts has no apparent effect on improving rock deformation and support load Advice on construction was proposed that main parts to be reinforced are drifts (its foot depth,connection parts with tunnel,and its corners) and core soil should be kept if rock is unsteady and needs reinforcing  相似文献   

3.
Water Supply Project in the Central City of Jilin Province is a large scale project which involves complex geological condition and high technical difficulties. In order to maximize the water delivery, the overlength pressure hydraulic tunnel is introduced. Based on detailed geological survey and other reliable technical references, this project can be treated as a demonstration in terms of how to lay large diameter TBM through a karst area with limestone. The in situ test is introduced to test the non bonded pre stress circumferential anchor tunnel structure and culvert structure when the water transmission engineering line crosses the shallow buried valley section. The Class Ⅰ and Class Ⅱ granite tunnels excavated by TBM is not aligned with saving project investment and speeding up construction progress. The BQ method is introduced to analyze the rock quality classification of long tunnels. There are not many domestic engineering examples of the above mentioned key technologies, and there are no mature theories and experiences to refer to. Based on theoretical research, numerical calculations, model tests, and productive in situ tests, those key technical problems of ultra long and pressurized tunnels are solved. This project has a great theoretical and engineering value.  相似文献   

4.
A sea crossing tunnel is generally large in scale, having a complex site environment, and lack of engineering experience. The success of the project is directly related to the design plan. At present, no metro sea crossing tunnel havd been built in mainland, and the design standard and technology of the sea crossing tunnel are not studied throughly. The key technology of long and large sea crossing metro tunnel design, including construction method selection, cross section design, waterproofing and drainage system design, response to complex environment in sea area, durability design, ventilation and evacuation are analyzd with methods of geological analysis, engineering analogy and comprehensive comparison based on the sea crossing tunnel of Xiamen Rail Transit Line 3. A combination of shield and mining methods is proposed for the geological conditions of different sections. The drainage system of the mining section can be maintained by applying advanced grouting to control displacement. The complex geology of the sea area is considered in the targeted design, including a deep weathering trough, a water rich sand layer, a hard rock and uneven stratum, and the development of solitary rocks. The durability design of the tunnel structure and the limit of the bearing capacity are treated equally to consider safety reserve. The tunnel adopts sectioned longitudinal ventilation and smoke extraction mode, and contains ventilation shafts and civil smoke extraction air shafts on shore to prevent disasters. The conclusions can provide technical support for tunnel scheme decision and reference for similar projects.  相似文献   

5.
LI Bo  BAO Zhen 《隧道建设》2019,39(5):820-831
The author focuse on the great challenges encountered during the tunneling process in the Wuhan Sanyang Road Tunnel, and the key techniques adopted to solve those problems. When tunneling in composite strata, engineers inevitably face problems such as inefficient excavation, excessive tool wear, excavation face instability and the risk of clogging. The TBM used in the project allows tool change under atmospheric pressure, which improves the efficiency of tool change and eliminated the risk of casualties during hyperbaric interventions. In terms of the tool wear and clogging, the authors propose technical solutions as follows: the optimization of the tool′s type and configuration, improvement of the central flushing system and chemical dissolution of clogging. The results indicate that through the countermeasures proposed, the tunneling efficiency can be improved effectively. They also reduce the cutter change frequency and eliminate the risk of TBM downtime. The technical achievements obtained in the construction of the Wuhan Sanyang Road Tunnel can provide technical reference for the construction of large diameter shield tunnels in composite strata in the future.  相似文献   

6.
LI Ning  LI Guoliang 《隧道建设》2018,38(3):481-493
Lanzhou Chongqing Railway is located in the uplift margin of the Tibetan Plateau, where the geological environment is very complicated and special. Based on numerical analysis and field tests, the physical and mechanical properties, micro structure, and complicated water related stability of the Tertiary sandstone are studied. A comprehensive dewatering system integrating deep surface wells and vacuum light well points in tunnel is used and the construction technique featured with advance reinforcement by horizontal jet grouting for the full face of aquiferous silty fine sand tunnels is invented to solve the problem of the Tertiary quick sand. In addition, the classification method for deformation potentiality in design and dynamic adjustment in construction of tunnels in high geostress soft rock is established, the deformation control technology combining active stress release and passive control according to the deformation mechanism is developed, an automatic real time monitoring system for operation is invented, and a complete technological system of design, construction, and operation management of soft rock tunnels is built. Moreover, the TBM equipment parameter design principles are put forward, the parallel lining and multi stage belt conveyor mucking system is researched, the phased ventilation technology is invented and thus the problem of safe and fast long distance construction by large diameter TBMs is solved. The technological achievements have filled in gaps and facilitated development of the tunnel construction technology.  相似文献   

7.
The large span transition section at Badaling Great Wall Station with a maximum excavation span of 32.7 m and an excavation area of 494.4 m2 is the traffic tunnel with the largest excavation span and excavation section area in the world, resulting in substantial construction difficulty and high safety risk. To ensure the construction safety of Badaling Great Wall Station, the support parameter design, a new excavation method, and the surrounding rock deformation control principle for tunnels with an ultra large section are studied. The study results show that: (1) According to the checking calculation, the support system had a safety factor of 1.16-2.46 during the construction period and 1.59-3.54 during the operation period, i.e., its engineering structure is safe and reliable. (2) The innovative triangle type excavation applied to the tunnel with an ultra large span and section has the advantages of a simple and clear method, safe and reliable structure, high applicability of mechanical equipment and high construction efficiency. (3) Depending on different surrounding rock classes and spans, the criteria for total deformation control of the large span transition section at Badaling Great Wall Station are as follows: in the case of class Ⅱ surrounding rock, the total settlement is 20-30 mm, and the total horizontal convergence is 15-20 mm; in the case of class Ⅲ surrounding rock, the total settlement is 30-40 mm, and the total horizontal convergence is 20-25 mm; in the case of class Ⅳ surrounding rock, the total settlement is 60-90 mm, and the total horizontal convergence is 40-55 mm; in the case of class Ⅴ surrounding rock, the total settlement is 130-190 mm, and the total horizontal convergence is 90-105 mm. (4) According to the numerical simulation, the innovative triangle type excavation method results in deformation that is mainly centralized in the tunnel arch making stage, accounting for approximately 95% of the total, followed by deformation in the side making stage, accounting for 4% of the total, with the smallest deformation only accounting for 1% in the inverted arch making stage.  相似文献   

8.
In recent years, with the help of good national policy support, the design, manufacturing and construction technology for tunnel boring machine (TBM) in China have been greatly improved; but compared with foreign relatively proven technology, there is still a certain gap for domestic technology development and engineering application. Based on the situation analysis of research and application of TBM in China and abroad, the research work for TBM design is carried out according to the complex geological conditions of Gaoligongshan Tunnel on Dali Ruili Railway as follows. (1) The prototype disc cutter rock breaking and scaled disc cutter wearing experiment are carried out to provide reference for adaptable design of TBM cutterhead and key parameter calculation. (2) The TBM design scheme is discussed from the aspects of high efficiency rock breaking of cutters and cutterhead, TBM over excavation, integrated support system, etc. (3) Two kinds of advanced geological prediction technology, i.e. HSP method and RTP method, are researched. The study results can provide reference for design and manufacture of TBM with high adaptability in complex geology and construction application in Gaoligongshan Tunnel.  相似文献   

9.
For the water conveyance tunnels in the long distance water diversion projects constructed or planned in China, most of them have to pass through mountain areas with complex geological conditions, due to the constraints of route selection. These tunnels might face engineering problems such as harsh natural environment, high seismic intensity and steep terrain, leading to difficulties in construction and high operational risks. In this paper, some key technical issues on the construction of ultra long deep buried water conveyance tunnels under complex geological conditions are summarized into 5 aspects, namely, (1) exploration and testing techniques for deep buried tunnels, (2) prediction and prevention for large deformation and rock burst in the surrounding rock masses, (3) failure mechanism and anti faulting techniques of the surrounding rock masses and lining for tunnels crossing active faults, (4) synergistic load bearing mechanism and life cycle design theory for rock support system of deep buried tunnels, (5) disaster treatment for deep and long tunnels such as prevention of high pressure water inrush. The scientific and technical problems to be solved and their development directions are pointed out, which can provide some reference for engineering construction of ultra long deep buried tunnels.  相似文献   

10.
The total length of the 2nd stage water transfer project in the northern area of Xinjiang of China is 540 km. The project consists of three tunnels, namely Xi Er (XE) Tunnel, Ka Shuang (KS) Tunnel and Shuang San (SS)〖HJ6.5mm〗 Tunnel, with lengths of 139.04 km, 283.27 km and 92.15 km respectively. All of these three tunnels have deep cover and are super long tunnels, and 95.6% of the total length of these three tunnels is constructed by TBMs. KS Tunnel is the longest water tunnel built or under construction in the world. In the paper, the trial TBM boring scheme and schedule of the water transfer project are introduced; the geological conditions revealed are statistically analyzed; and main project difficulties, i.e. durability of key equipment in long distance driving, passing through fault and fracture zones, water inrush, single head ventilation and transportation in long distance tunneling, anti slope drainage, and rock breaking efficiency and boring efficiency, are put forward. The adaptability of the TBMs used is analyzed from the aspects of adaptability to different surrounding rocks, adaptability to bad geological conditions and countermeasures, long distance ventilation and belt conveyor mucking and countermeasures, and TBM boring stability (such as equipment availability, boring time proportion, system malfunction and operation time). The following conclusions are obtained: (1) Accurate geological survey is the precondition of efficient tunneling. (2) The open type TBM can better adapt to Grade Ⅱ and Ⅲ of surrounding rocks, jointed and fractured zones and small faults; the adaptability of the TBMs used to the large scale fault fracture zones and water rich strata in this project is poor, and it needs to be improved in aspects of TBM equipment, supporting and construction technology. (3) The average availability of the TBM equipment in the trial boring stage is 89.9%, however, the malfunction rate of some ancillary equipment is high, particularly oil leakages occur to the main bearing seals; in order to achieve long distance tunneling, it is necessary to further improve the reliability and durability of the TBM equipment. (4) The average net boring efficiency in the trial boring stage is 296%, and TBM1 in Section Ⅱ of SS Tunnel achieves up to 45.2 % net boring efficiency; and highest monthly progress rate is 1 280 m, which created the highest record of the open type TBM boring in China. (5) TBM need to make great efforts to achieve 90% of the equipment system′s availability and over 40% of the tunneling efficiency.  相似文献   

11.
SUN Jun 《隧道建设》2018,38(11):1753-1764
The author discusses the necessity and urgency of constructing the Bohai Bay Crossing Corridor from the following aspects such as the increasing traffic volume, the convenience of the transportation after the corridor is constructed, and the regional benefit brought by the corridor. As for the timing of the construction of the sea crossing corridor, the author thinks that as long as the national economic situation permits and relevant conditions are basically available, the preliminary work should be carried out as soon as possible so as to promote the early commencement of the construction. Regarding the proposal of building another coastal national highway/high speed railway along the Bohai Bay coast, the author puts forward his viewpoints. In the aspect of construction risks, the author thinks that the geological risks in the construction of the Bohai Bay Crossing Corridor are very difficult to be dealt with; therefore, strict and detailed risk assessment should be carried out, and effective safety measures should be taken to mitigate the risks. The author also briefly describes the technological advantages of the tunnel proposal selected for the Bohai Bay Crossing Corridor, and briefly analyzes some key technological issues in the tunnel construction. The author describes the construction scheme and construction period estimation for the sea crossing corridor in details. The author makes the following proposal are given: (1)the hard rock tunnel boring machine (TBM) assisted by the drilling and blasting method should be used for the construction of the long sea crossing tunnel of Bohai Bay Crossing Corridor; (2) a parallel service tunnel shall be arranged between the twin main tunnel tubes; (3) in Proposal 2, the diameters of the twin main tunnel tubes and the service tunnel should be 8.0 m and 55 m, respectively. The proposal has two optional solutions: Solution 1: The service tunnel ( 55 m) located between the main tunnel tubes will be constructed first; for the main tunnel tubes, the disassembled TBMs ( 8 m) and the backup gantries are assembled for tunneling after arriving at the main tunnel tubes through the service tunnel and the cross passage; Solution 2 (alternative): Tunneling with  55 m TBM is carried out; the  55 m TBM will be dismantled to pass through the cross passage, and then be re assembled after arriving at the main tunnel; the start section (180 m) of main tunnel tube will be formed by  55 m TBM before it is enlarged to  8 m by drilling and blasting method; or the cross passage is enlarged to a large curved space to allow the 5.5 m TBM passing throught without disassembly. Comparison and contrast will be made and the preferred solution will be adopted. According to the rough estimation on the construction period of the 125 km long sea crossing tunnel, the total construction period of "completed tunnel" will be about 19 years (including 5 years of detailed offshore investigation) in Solution 1.  相似文献   

12.
Tsinghuayuan Tunnel of Beijing Zhangjiakou High speed Railway is the first fully prefabricated high speed railway tunnel in China. The supporting structure, subrail structure, and subsidiary structure of Tsinghuayuan Tunnel are all prefabricated in the factory. The strength, deformation and stability of subrail structure are analyzed by numerical simulation method; a kind of three block type of subrail prefabricated structure is put forward according to prefabricated assembling technology; and the subrail space is used to ventilate and rescue under the stability condition. The connection between subrail structure and shield segment is the key to fully prefabricated assembling technology. By introducing the grouting technology and construction keys of subrail structure, the stress on subrail structure and shield segment can be balanced. The results can provide reference for similar projects in the future.  相似文献   

13.
In this paper, the application status of foundation trench excavation and navigation channel dredging, dry dock construction, element precasting, element transport, element mooring, element immersion, joint treatment and foundation treatment of several typical immersed tunnels in China are introduced. And then the Honggu Immersed Tunnel in Nanchang and subsea tunnel of island tunnel project of Hong Kong Zhuhai Macao Bridge are taken as examples; and some innovations of key technologies, i.e. key construction technology, element transport and immersed technology, differential settlement control technology for element immersion, subsea connection technology, and subsea space development and subsea harbor construction technology, are summarized for river crossing and sea crossing immersed tunnels. Finally, the development trends of immersed tunnels are prospected based on new technologies and equipments from the aspects of prolongation of immersed tunnel, field breakthrough, urban construction promoting and traffic demand adding of cities along rivers and seas. The results can provide reference for construction and popularization of immersed tunnels.  相似文献   

14.
With reference to the construction conditions and features of metro tunnels, the design features of double shield TBMs are analyzed and key issues to be considered and settled when a double shield TBMs is used for metro tunnel construction are proposed. The issues include cutterhead′s rock breaking capacity, small curve excavation, selection of backfill grouting technology and jamming prevention and release function in fault and fracture zone, etc., which all have a direct effect on the geological adaptability, tunnel lining quality and tunneling performance of double shield TBMs. Subsequently, the specific design and optimization scheme, which includes the design of cutterhead thick steel plates, tapered shield, monorail hoist and pea gravel backfill and cement slurry grouting, etc., are studied. The success of double shield TBMs in Shenzhen Metro project well proved its remarkable geological adaptability and advantages in efficient mechanized construction.  相似文献   

15.
杭州狭长软土基坑支护侧移规律与解析预测方法研究   总被引:1,自引:0,他引:1  
In order to reduce the influence of deep narrow foundation pit construction on adjacent properties in urban area in Hangzhou, the characteristics of the support wall lateral deflection are analyzed and the corresponding analytical prediction method is proposed. The support wall lateral deflections of the deep narrow foundation pits at Wenyi West Road, Qingchun Station, Qiutao Station, Xingtang Station and Qingnian Station in Hangzhou soft clay are monitored and compared with those of deep foundation pits in Zhejiang and deep narrow foundation pits in Shanghai, Taipei and Singapore. The results show that the maximum support wall lateral deflection of the foundation pit on Wenyi West Road, 0.20%He ~0.25%He, where He is the maximum excavation depth, is close to that in Shanghai(0.15%He~0.41% He), but is smaller than those in Zhejiang, Taipei and Singapore(0.27% He~0.62% He); which is related to the high tangential modulus of Hangzhou soil and small width of the foundation pit. The support wall lateral deflection of the narrow deep foundation pits in Hangzhou can be precisely predicted based on the representative stress strain relationship at site and the modified mobilisable strength design (MMSD) method.  相似文献   

16.
TAN Shunhui  SUN Heng 《隧道建设》2019,39(7):1073-1082
By analyzing the application cases of super large diameter shield machine in the world and taking China Shantou Gulf Tunnel and Shenzhen Chunfeng Tunnel construction for examples, the problems encountered in the research and development and construction are proposed and the key technologies to solve a series of problems, such as cutterhead maintenance and cutter changing technology under high soil and water pressure, boring in long fractured zone, are explored. More specifically, the technologies mainly involve cutterhead design, atmospheric cutter changing, main drive with telescopic and swinging function, reliable sealing system, anti blockage technique by applying double crushers, which are of great significance to the development and application of super large diameter shield machine.  相似文献   

17.
To ensure the safe, rapid and high quality construction of Zhengzhou Wanzhou High speed Railway, a series of exploration and innovation of construction technology, structural design and information management under the condition of large scale mechanization is used in the whole construction process. The technology includes: (1)A set of advanced geological prediction, advanced pre reinforcement technology of excavation face, mechanized construction technology of primary support, wide waterproof board trolley operation technology and intelligentized full face lining trolley of large scale mechanized construction technology are formed. (2)A classification method of surrounding rock stability is established based on the mechanized construction technology, and the design parameters of the tunnel support structure are optimized under the guidance of New Austria Tunneling Method. (3)To realize informatized management of tunnel construction, the tunnel construction management system, construction information record system, construction safety management system, quality management system of concrete mixing station and quality credit evaluation system are established. Finally, on the basis of mechanized and informatized construction, exploration and outlook of the tunnel intelligentized construction technology are given from the aspects of the dynamic intelligentized design system of tunnel support system, the intelligentized robot construction technology of tunnel support system and the intelligentized monitoring system of tunnel structure, to promote China′s tunnel construction technology.  相似文献   

18.
吴乐 《隧道建设》2010,30(4):465-468
No. 2 ventilation shaft of Kuocangshan tunnel on Zhuji Yongjia expressway has complex geologic condition, many construction difficulties and short construction schedule. In order to complete the project on time, the construction technology of "muck dropping shaft sinking and secondary enlarging excavation" is selected for the sinking of the shaft from several shaft sinking methods, including conventional one time shaft sinking method, "muck dropping shaft sinking and secondary enlarging excavation" method and raise boring method. The selected construction technology is presented in this paper. This technology not only achieves good results in construction schedule, construction safety and construction quality, but also reduces the construction cost.  相似文献   

19.
Four methods of erecting steel stiffening truss girder of suspension bridge,including the deck lifting gantry crane method,the cable-mounted crane method,the cantilever erection method with derrick crane and the incremental launching method,were studied Based on construction conditions of the bridge,according to the optimal combination of various factors such as construction safety,quality,period,environmental protection and economic performance,etc,the cantilever erection method with derrick crane was recommended for the bridge. On this basis,three categories of connection in cantilever erection methods,including the all hinged method,the successive fully splicing method and the successive splicing with temporary erection hinge method,were studied The successive splicing with temporary erection hinge method was recommended in the bridge with consideration of the requirements of construction safety,quality and time limit In addition,the traction method of hangers at the top end during cantilever erection was studied Finally,the erection method of three key  stages,including the first segment near the pylon,the standard segment,as well as the closure segment of steel stiffening truss girde,r was studied. The cantilever erection method with derrick crane provides a new way for design and construction of long-span suspension bridge with steel stiffening truss girder in the western area of China  相似文献   

20.
In order to assess temperature field in microwave heating for recycling asphalt pavements,a 2D mathematic heat transfer model was developed based on Fourier heat transfer theory The microwave internal heat?generation was researched by using surface field of pyramidal horn replacing approximate radiation field In addition,the boundary conditions were built and normalization processing was implemented The control volume based finite differential method (CV-BDM) was used to establish the implicit discrete scheme of the conservation equations,and the numerical value simulation was employed By continuous or intermittent  radiation heating technique,a microwave heating experimental system at 2 145 GHz was carried out to investigate temperature variation characteristics of asphalt pavements along with heating time The result shows that (1) the increase of temperature of asphalt mixture during microwave heating is obviously nonlinear,the temperature rises slowly in the initial stage of the heating but increases rapidly in the late heating period; (2) the temperature distribution is non-uniform that the temperature in central area of the surface is higher while it is lower on edge; (3) the uniformity of temperature within asphalt mixtures can be improved by using intermittent heating technique,and the heating time must be reasonable The simulation results are in preferable agreement with the experiment  相似文献   

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