China Railway Tunnel Group Co.

Luoyang, China

China Railway Tunnel Group Co.

Luoyang, China
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Wang M.,China Railway Tunnel Group Co. | Liu D.,Southwest Jiaotong University | Liu D.,Key Laboratory of Transportation Tunnel Engineering
Modern Tunnelling Technology | Year: 2016

Based on the Hongzhuanlu jacking pipe tunnel project underneath Zhongzhou Avenue in Zhengzhou City, we studied the influence of changing contents of materials-including bentonite, CMC, soda ash and PHP-on the properties of a thixotropic slurry, then determined its mix proportions. Furthermore, we also studied the technologies of slurry preparation, grouting equipment selection, grouting parameter design, the arrangement of grouting holes, synchronous grouting and secondary grouting and surface waxing of tunnel elements per the situation of field construction. The theoretical calculation and field testing showed that after applying resistance reducing technologies the values of the maximum jacking force and the average friction resistance coefficient for the vehicle tunnel tube with a large cross section is reduced by 56.3% and 62.3%, respectively, and 56.7% and 60.9% for the non-vehicle tunnel tube with a small cross section, which indicates that these technologies are effective. © 2016, Editorial Office of "Modern Tunnelling Technology". All right reserved.


Liu Z.,China Railway Tunnel Group Co. | Shi C.,Central South University | Peng Z.,China Railway Tunnel Group Co. | Ouyang G.,China Railway Tunnel Group Co.
Modern Tunnelling Technology | Year: 2016

Considering that underwater tunnels are important river-crossing passages in urban areas at present, and using the construction of the Yingpan road tunnel in Changsha city as an example, some innovative design and construction methods are discussed for urban underwater bored tunnels. A method for determining minimum overburden is put forward based on the consideration of engineering control measures and analysis of the problems with existing methods, by which the minimum overburden is determined to be 11.5 m (more than 5 meters shallower than under existing methods in China and abroad) and the tunnel length is reduced by nearly 400 m accordingly. The water seepage during tunnel operation could be reduced by adopting a"blocking-based limited drainage"principle and adjusting grouting-ring thickness and relevant reinforcement parameters. A shallow-buried large-section underwater tunnel with a depth/span ratio of 0.46 and excavation area of 376 m2 is completed successfully using advance full-face pre-reinforcement, a double-layer primary support, a reasonable excavation section division, and proper construction arrangements. © 2016, Editorial Office of "Modern Tunnelling Technology". All right reserved.


Feng H.,State Key Laboratory of Shield Machine and Boring Technology | Feng H.,China Railway Tunnel Group Co. | Chang X.,China Railway Tunnel Group Co.
Modern Tunnelling Technology | Year: 2016

The structural safety of shield tunnels is fundamental for urban rail transit. Therefore, tunnel disasters need to be controlled immediately whenever they occur, otherwise they will be a serious threat to the tunnel's structure and operation. For this reason, prevention and control of structural disasters is the most important issue for a tunnel's structural safety. Since there is an increasing number of tunnel defects occurring in the tunnels operated in Shanghai and Nanjing, this paper classifies the structural disasters into four categories based on a contrastive analysis of shield tunnel projects (i.e., longitudinal uneven settlement, convergence and deformation, water leakage and structure damage) and presents a detailed analysis and discussion of the occurrence mechanism of each disaster as well as treatment measures and suggestions. Additionally, it details the key technologies and processes commonly used in tunnel disaster prevention and control, such as steel fiber reinforced concrete and instant sealing with chemical grouts. Finally, it predicts the future development of shield tunnel structural disaster prevention and control in China in terms of concepts, systems, mechanism construction and technical breakthroughs. © 2016, Editorial Office of "Modern Tunnelling Technology". All right reserved.


Wang M.-S.,China Railway Tunnel Group Co.
Journal of Railway Engineering Society | Year: 2017

Research purposes: According to the area environment characteristics of Beijing and process characteristics of hole-pile method, this paper aims at the construction shaft setting mode, cross channel setting mode, pilot tunnel design, steel pipe pile design, buckle arch design for a systematical study of hole-pile method, further explores the hole-pile method application of boundary conditions in terms of design, further researches to explore the key technology and key measures in design and construction of beijing subway station, sums comprehensive technical guidance of the hole-pile method up, in order to provide a reference for future similar metro engineering construction. Research conclusions:(1)The main idea of hole-pile method is forming vertical bearing structure as soon as possible. (2)Hole - pile method has the advantages of flexibility, good adaptability, which is suitable for the undercut subway station construction under complex environment. (3)Systematic research of hole - pile method design and construction is hysteretic, which needs to be further researched. (4) The results of this paper can provide reference for the subway station design with hole - pile method under complex environment. © 2017, Editorial Department of Journal of Railway Engineering Society. All right reserved.


Zhang Y.-J.,CAS Wuhan Institute of Rock and Soil Mechanics | Yang C.-S.,China Railway Tunnel Group Co.
Journal of Central South University of Technology (English Edition) | Year: 2012

The models of stress corrosion, pressure solution and free-face dissolution/precipitation were introduced. Taking a hypothetical nuclear waste repository in an unsaturated dual-porosity rock mass as the calculation objective, four cases were designed: 1) the fracture aperture is a function of stress corrosion, pressure solution and free-face dissolution/precipitation; 2) the fracture aperture changes with stress corrosion and pressure solution; 3) the fracture aperture changes with pressure solution and free-face dissolution/precipitation; 4) the fracture aperture is only a function of pressure solution, and the matrix porosity is also a function of stress in these four cases. Then, the corresponding two-dimensional FEM analyses for the coupled thermo-hydro-mechanical processes were carried out. The results show that the effects of stress corrosion are more prominent than those of pressure solution and free-face dissolution/precipitation, and the fracture aperture and relevant permeability caused by the stress corrosion are only about 1/5 and 1/1000 of the corresponding values created by the pressure solution and free-face dissolution/precipitation, respectively. Under the action of temperature field from released heat, the negative pore and fracture pressures in the computation domain rise continuously, and are inversely proportional to the sealing of fracture aperture. The vector fields of flow velocity of fracture water in the cases with and without considering stress corrosion are obviously different. The differences between the magnitudes and distributions of stresses within the rock mass are very small in all cases. © 2012 Central South University Press and Springer-Verlag Berlin Heidelberg.


Zhang Y.-J.,CAS Wuhan Institute of Rock and Soil Mechanics | Yang C.-S.,China Railway Tunnel Group Co.
Yantu Lixue/Rock and Soil Mechanics | Year: 2012

On the basis of using the models of stress corrosion and pressure solution established by Yasuhara et al, the solute concentration field is introduced into the 2D FEM code of thermo-hydro-mechanical coupling analysis for dual-porosity medium developed by the authors. Aiming at a hypothetical nuclear waste repository in unsaturated rock mass from which there is a nuclide leak, two computation conditions are designed: (1) the fracture apertures are changed with the stress corrosion and pressure solution (the porosity of intact rock is also a function of stress); (2) the fracture apertures and the porosity of intact rock are constants, then the corresponding two-dimensional numerical simulation for the coupled thermo-hydro-mechano-migratory processes is carried out; and the states of temperatures, rates and magnitudes of aperture closure, pore and fracture pressures, flow velocities, nuclide concentrations and stresses in the rock mass are investigated. The results show that the aperture closure rates caused by stress corrosion are almost six orders higher than those caused by pressure solution; and the two kinds of closure rates climb up and then decline, furthermore tend towards stability; when the effects of stress corrosion and pressure solution are considered, the negative fracture pressures in near field rise very high; the fracture aperture and porosity decrease in the case 1, so the relative permeability coefficients reduce; therefore the nuclide concentrations in pore and fracture in this case are higher than those in case 2 because the effects of negative pore and fracture pressures on the stress balancing are not reckoned in; the magnitudes and distributions of stresses within the rock mass in two calculation cases are almost the same.


Wang H.,China Railway Tunnel Group Co. | Wang H.,Southwest Jiaotong University
Yantu Lixue/Rock and Soil Mechanics | Year: 2011

Combined with engineering geological conditions of bridge foundation slope, deformation and failure process on the condition of natural state and loading is simulated and analyzed by floor-friction test method based on similarity principle qualitatively. The test results indicate that the rock masses of slopes at left and right banks are in stable state under the condition of natural state; under the condition of loading rock mass in left bank is in stable state; but the scattered earth-body in right bank is unstable; so that the right bank slope is in unstable state. A measure is suggested by pre-reinforcement or changing the location of bridge pier.


Li Y.,China Railway Tunnel Group Co. | Li Z.,China Railway Tunnel Group Co. | Wang Q.,China Railway Tunnel Group Co. | Jiao L.,China Railway Tunnel Group Co.
Modern Tunnelling Technology | Year: 2013

In order to ensure the safety of subsea tunnel construction in a soft fractured stratum, advanced geological forecasting was performed and the selection standard of grouting schemes, grouting material, grouting parameters, grouting technology, and a grouting effect test were analyzed and summarized in light of the characteristics of this stratum. This paper discusses the general scheme of grouting reinforcement and water-stoping technique for mined subsea tunnels in weak, broken strata and describes its applications in the Qingdao Jiaozhou Bay and Xiamen Xiang'an subsea tunnels.


Zhang M.,China Railway Corporation | Sun G.,China Railway Tunnel Group Co. | He Z.,China Railway Corporation | Gao G.,China Railway Tunnel Group Co.
Modern Tunnelling Technology | Year: 2013

During construction of the Zhongtianshan tunnel, a developed joint zone was encountered with water pressure of up to 6.3 MPa and a water inflow of 500 m3/h/probing hole, causing a flood disaster in the tunnel. In this context, the principle of "drainage reduction by grouting and depressurizing by dewatering" was adopted. The grouting and dewatering design parameters, the new hole-drilling technology with "high pressure percussion drilling," and the new grouting technology with simultaneous grouting and discharging at the same working face are described in this paper. Prospective effects of water blocking by grouting are achieved based on the analysis of a P-Q-t curve, water inflow in the drilling hole, water inflow in the testing hole, and stability in the testing hole, ensuring the success of tunnel construction.


Liu C.,Fuzhou University | Liu Z.,China Railway Tunnel Group Co.
Modern Tunnelling Technology | Year: 2014

Water inrush often occurs during tunnel construction in karst areas due to their complexity, and this frequently results in surface settlement. This paper proposes an analytical method for construction in a karst development zone in light of water inrush induced surface settlement, namely to analyze the features of the surface settlement with a settlement diagram, to determine the geological structures of the karst development zone, to study the zone's boundary with geological data related to the settlement area, and to analyze the supply relation between the water inrush and rivers according to the relationship between the settlement centre and the rivers. Additionally, using the data of surface settlement induced by water inrush at YDK24 +098 of the Xiangshan tunnel on the Longyan-Xiamen railway, this paper analyzes the geological structures of the karst development zone, the longitudinal boundary of the karst, and the supply relation between the water inrush and the rivers, thereby verifying the feasibility of the above mentioned analytical method.

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