[an error occurred while processing this directive]

Home | About Journal |  Editorial Board |   |  Instruction |  Subscription |  Advertisement |   |  Download |  中文  Office Online   Search     Adv Search

·Online Submission ·Manuscript Tracking ·Peer Review ·Editor Work ·Office Work ·Editor-in-chief  Journal Online ·Forthcoming Articles ·Current Issue ·Next Issue ·Archive ·Advanced Search ·Read Articles ·Download Articles ·Email Alert ·  Download · More>>

Quick Search     Advanced Search MODERN TUNNELLING TECHNOLOGY   2017 Vol.54 Issue.1 Published 2017-02-25 Article 1 Key Techniques for the Auxiliary Air Pressure Balance Mode for Shield Tunnelling ZHU Wei-Bin- 1 Zhong-Chang-Ping- 2 Huang-Wei-Ran- 2 He- Ting- 1 Zhang-Bu-Ling- 3 Zhu-Si-Ran- 2 As for the rock ground with large overburden and developed rock fisser water as well as the mixd ground with rich water and airtightness, the blow-out event often occurs due to a large shield load and quick wearing of cutting tools when conventional full earth pressure driving mode is adopted, which results in low efficiency and poor-quality simutaneous grouting. The definition of the“air pressure balance”mode and its advantages and disadvantages are presented based on practical experience with the Guangzhou Metro lines 1, 2, 3 and 13Additionally, key techniques for“air pressure balance”driving mode are studied, secondary risks concerning this driving mode are analyzed and measures for prevention and countermeasures for emergencies are given in this paper. 2017 Vol. 54 (1): 1-8 [Abstract] ( 1306 ) [HTML 1KB] [ PDF 2414KB] ( 2397 ) 9 On Some Issues with Concrete during Tunnelling by the Mechanical PreCutting Method HAN Gao-Sheng- 1 Wang-Xiu-Ying- 2 Wang-Bei-Hua- 2 Using the concept of protection by shield shell and flexibility of NATM for complex geology, large-sec? tion excavation is possible under the protection of a pre-built arch using the mechanical pre-cutting method, which has obvious advantages in low-strength sand and soil strata approaching construction. Regarding the problem of difficult spraying and pouring of concrete in the slot, such special requirements as concrete strength and other properties are discussed based on an investigation and calculation analysis. It is concluded that the compressive strength of concrete in the slot after 8 hours should reach 12 MPa for a double-track loess tunnel with a large section; the traditional concrete spraying equipment needs to be improved, and the mixing ratio of concrete should be optimized and an indoor experiment for concrete in the slot should be compared with the coring test at the site. 2017 Vol. 54 (1): 9-16 [Abstract] ( 1315 ) [HTML 1KB] [ PDF 2671KB] ( 2329 ) 17 Design of a Structure Health Monitoring System for Shield Tunnels and Some Key Issues LI Xiao-Jun- 1, 2 , 3 Hong-Bi-Chen- 3 Yang-Zhi-Hao- 4 The operation of shield tunnels typically lasts for 50~100 years. Recently, the Structural Health Monitor? ing System (SHMS) for shield tunnels has received much attention with more and more river-crossing deep-buried large-diameter long-distance shield tunnels being built in China. Based on a comprehensive review of the current SHMS for tunnels, and considering the design characteristics of shield tunnels, a clear definition is put forward for a Shield Tunnel SHMS (STSHMS). A STSHMS is a data acquisition, management and analysis system for shield tunnels, which uses long-term monitoring techniques, data analysis and mechanical analysis, with the aims to verify key design parameters and index, assess and evaluate structure performance and provide a basis for allocating Maintenance and Rehabilitation (M&R) resources. The STSHMS comprises three subsystems, i.e., a data acquisitiontransmission-storage subsystem, a data integration- visualization-warning subsystem, and a data analysis-assessment subsystem. The main contents and design approach of each sub-system are introduced, with a discussion of key issues of determination of monitoring items and locations, sensor selection, data integration, visualization, development of health assessment methods and the relationship with M&R, as well as the engineering practice of developing STSHMS in the Shanghai Yangtze River Tunnel Project. Finally, some concrete suggestions are provided for the design and implementation of STSHMS. 2017 Vol. 54 (1): 17-23 [Abstract] ( 1396 ) [HTML 1KB] [ PDF 1242KB] ( 2192 ) 24 On the AHP-Based Design and Application of Waterproofing and Drainage for Subway Tunnels LUO Jian-Jun- 1 Lei- Gang- 2 Hua-Fu-Cai- 2 Proper evaluation and correct selection of the waterproofing and drainage types for metro tunnels is an effective way to reduce water leakage during tunnel operation. Regarding selection of waterproofing and drainage patterns, normally a single evaluation factor of water inflow is used for evaluation and analasis instead of comprehensive evaluation system. Based on previous studies of waterproofng and drainage of metro tunnels, an AHP-based judgement system for types of waterproofing and drainage is put forward, a mathematical evaluation model of the analytic hierarchy process is established, weights of the hierachy index affecting influential factors of waterproofing and drainage in metro tunnels are determined, and quantification of the types of waterproofing and drainage is achieved with established criteria and standards. Practical cases show that the fuzzy synthetic evaluation method is consistant with the actual situation. Further study and verification are required for this application using a concrete project. 2017 Vol. 54 (1): 24-30 [Abstract] ( 1164 ) [HTML 1KB] [ PDF 1541KB] ( 2400 ) 31 On Adaptability Assesment of a TBM Used in Urban Subways 吕Rui-Hu In order to gain essential detailed data for future selection of TBM type, to research the adaptability of a TBM used in urban subway tunnels, and to implement the transition from quantitative adaptability analysis to qualitative and quantitative adaptability analysis, the TBM test section of Chongqing Rail Transit line 6 phase I is used as an example to explore TBM adaptability assessment criteria based on the evaluation index system which is built by a comprehensive contrastive analysis of influencing factors of the adaptability assessment, with the scores and weights of numerous evaluation indexes determined by the analytic hierarchy process and the engineering analogy method. The adaptability of the TBM used in the urban subway was synthetically evaluated by the final assessment criteria. The conclusion and suggestions are as follows: 1) the adaptability of the TBM used in this project is evaluated as A-excellent; 2) the adaptability evaluation index system of the TBM method should be adjusted regarding different projects; 3) further in-depth study should be performed for the scores of the TBM adaptability evaluation index; and 4) with the update of engineering information, the adaptability assessment criteria should be revised and improved correspondingly. 2017 Vol. 54 (1): 31-39 [Abstract] ( 1218 ) [HTML 1KB] [ PDF 1398KB] ( 1920 ) 40 Experimental Study on Suppressing and Extinguishing of a Diesel Oil Pool Fire with the Water Mist System in a Large-Section Tunnel LI Tao- 1, 2 Zhang-Yu-Chun- 2 Ma- Jian- 1 Xiao- Han- 2 A 1∶10 reduced-scale model test was conducted based on Froude similarity criterion to study the varia? tion of physical parameters under different operating pressures at the nozzle in the course of extinguishing a diesel oil pool fire with water mist, especially the variation law of temperature at the ceiling above the fire source, the vertical temperature of the fire plume, the radiation intensity of the fire zone and the longitudinal smoke temperature with or without the water mist. The results show that the maximum vertical temperature appears in the continuous flame zone at 20 cm above the fuel surface for a weak flume fire, and the fatalness of the fire is the most serious in the interim and later stages. The working pressure of the water mist at the nozzle is divided into water mist pressure without fire control (0.2 MPa), water mist pressure with fire control (0.4 MPa) and fire-extinguishing water mist pressure (0.6 MPa, 0.8 MPa) based on testing and temperature data. The densities of the mixture of water vapor and smoke flowing at the tunnel crown as well as the smoke concentration are reduced under the continuous function of a water mist and fire plume. As for the longitudinal smoke temperature change at the tunnel crown, it is divided into large amplitude attenuation and steady attenuation areas. The fire plume temperature decreases obviously during fire control with the water mist, and the flame temperature is below ignition temperature after cooling 2017 Vol. 54 (1): 40-47 [Abstract] ( 1341 ) [HTML 1KB] [ PDF 3696KB] ( 2147 ) 48 On a Driver′s Visual Reaction to Different Coatings on Tunnel Sidewalls HE Shi-Yong- 1 Liang- Bo- 1, 2 Luo- Hong- 3 The horizon in front of a driver has a direct relationship with how the driver prejudges and treats danger? ous conditions. Highway tunnel sidewalls are an important part of the visual field of a driver and have an impact on driving safety. A spectroradiometer luminance meter was used to test the lighting parameters of different sidewall coatings, and lighting environments with the same lighting parameters and different sidewall coatings were simulated. Using this highway tunnel lighting simulation and an effect evaluation device, the effects of three coatings on a driver′s visual perception performance were evaluated based on reaction time, and a new method of highway tunnel lighting was explored regarding driving safety and energy savings. The result shows that the lighting environment can be significantly improved by using energy-storage and self-luminous materials for the tunnel sidewall; under the same LED lighting conditions, the driver′s visual performance is improved by using the coatingg material with high reflectance and yellow and green components in the reflective spectrum and it is thus favorable in terms of driving safety and energy savings for highway tunnels. 2017 Vol. 54 (1): 48-54 [Abstract] ( 1216 ) [HTML 1KB] [ PDF 2352KB] ( 2261 ) 55 Geological Structures Inclined to Hazards due to Water Burst in Tunnel construction and Their Classifications GUO Ru-Jun- 1, 2 He-Fa-Liang- 2 It has the features of popularity, abruptness and severity for the water burst during tunnel construction, and so wide attention has been paid to it in the field of tunnelling. On the basis of previous experiences with the relationship between hazards due to water burst and unfavorable geological bodies, six kinds of structures that may cause hazards due to water burst are concluded, i.e. water-filled (mixture of mud and water) karst, strongly compres-so-crushed fractured zone in uncemented water-rich compressive fault, uncemented water-rich extensional fault,underground syncline water storage structure, water-rich bedding staggered (developed joint rock mass) fractured zone and abandoned water-filled mine. Three principles for classifications of hazard structures related to water burst are put forward regarding the structure constitutions, water-insulation rock block types and common engineering treatment measures, and it divides the structure inclined to hazard due to water burst into fully water-filled structure and fracture fissure/void water-bearing structure, and corresponding engineering treatment measures are presented. 2017 Vol. 54 (1): 55-60 [Abstract] ( 1310 ) [HTML 1KB] [ PDF 509KB] ( 2320 ) 61 Key Points of Potential Safety and Quality Hazard Troubleshooting for Chengdu Metro Construction GUO Jian-Xiang- Wang- Bing- Wang-Xiao-Jun- Yang-Jin-Qiu Metro construction involves issues of safety and quality. This paper briefly introduces the compilation basis and application conditions regarding the potential construction safety and quality hazards for the Chengdu Metro considering the technical state of metro construction safety and quality management both at home and abroad, as well as the main geotechnical problems and risks to be encountered in construction of the Chengdu Metro. This paper focuses on the key points of troubleshooting potential safety and quality issues for metro construction. 2017 Vol. 54 (1): 61-67 [Abstract] ( 1291 ) [HTML 1KB] [ PDF 1393KB] ( 2201 ) 68 Rock Mass Elastic Resistance Coefficient Measurement Based on the Seismic Wave Method YU Shi-Wei- 1 Liu-Cheng-Yu- 1, 2 The elastic resistance coefficient of surrounding rock is an important parameter of tunnel structure de? sign, and is characteristically difficult and expensive in terms of in-situ testing. A method is proposed for calculating the elastic resistance coefficient based on the measured seismic wave velocity of the surrounding rock in advance geological forecasts based on the seismic reflection method. Specifically, the dynamic elastic parameters of the surrounding rock are calculated using the measured seismic wave velocity, then the static parameters of the surrounding rock are calculated based on the relationship between the dynamic and static elastic parameters of the rock mass, and the elastic resistance coefficient of the rock mass is derived. Taking the Tingzhou tunnel of the Ganlong line as an example, it is determined that the coefficients of the tunnel surrounding rock of grade Ⅲ and Ⅳ are 0.54~1.19 GPa/m and 0.24~7.6 GPa/m respectively. The above calculated values are consistent with the data for elastic resistance coefficients of surrounding rock of grade Ⅲ and Ⅳ specified in the "Code for Design of Railway Tunnels." 2017 Vol. 54 (1): 68-73 [Abstract] ( 1280 ) [HTML 1KB] [ PDF 1408KB] ( 2141 ) 74 On the Diffusion Mechanism of Permeation Grouting under Hydrodynamic Conditions ZHANG Lian-Zhen- Zhang-Qing-Song- Zhang- Xiao- Li-Zhi-Peng- Wang-De-Ming- Zhao- Peng The flowing of groundwater has a significant impact on grout diffusion in the process of permeation grout? ing. Based on this phenomenon, the process of permeation grouting under hydrodynamic condition was described by two-phase seepage theory, and a numerical simulation was conducted by establishing a corresponding finite-element model to study the law of grout diffusion and the factors affecting the grout diffusion range. Results show that grout diffusion form is shaped in a“U”along the flow direction under the hydrodynamic condition, and the dynamic water field restricts the range of slurry diffusion; there are significant differences between lateral grout diffusion and longitudinal grout diffusion, and between grout diffusion with the flow direction and against the flow direction; grouting pressure and grout velocity decrease sharply near the grouting hole; the underground water flow field and grouting pressure are the main controlling factors affecting the range of grout diffusion; and the range of grout diffusion has a positive correlation with grouting pressure and a negative correlation with the velocity of the flowing water. Suggestions are proposed to improve the design methods and technologies of permeation grouting under hydrodynamic conditioin. 2017 Vol. 54 (1): 74-82 [Abstract] ( 1166 ) [HTML 1KB] [ PDF 3324KB] ( 2042 ) 83 A Simplified Calculation Method for the Wedge Model ZHAO Hong-Ze- 1 Zheng-Qun-Fei- 1 Zhu-Jian-Ming- 2 Gao-Xiao-Jiang- 3 There are so many parameters in theorectical calculation formulas for the limit support force of a shield excavation face, and the calculations are very complex. Based on the popular wedge calculation model, a simplified calculation for the limit support force was studied. The results show that the relationship between the logarithm lnσT of the calculated value and the internal friction angle φ of sandy soil is approximately linear when the internal friction angle is in the range of 20°~70°; and without considering the influence of additional stress on ground, the relation curve of lnσT and φ is approximately parallel under the different factors of sandy soil gravity, the diameter of the shield excavation face and the buried depth. A simplified calculation method for the limit support force of a shield excavation face was obtained by way of linear fitting and introducing the influence coefficients of the sandy soil gravity a, the diameter of the shield tunnel excavation face b and the buried depth c, which simplifies the solving process of the limit support force of a shield excavation face. 2017 Vol. 54 (1): 83-88 [Abstract] ( 1170 ) [HTML 1KB] [ PDF 2404KB] ( 1735 ) 89 Influence of Local Water Leakage of Shield Tunnels on the Pore Water Pressure of Soil Masses WANG Zhi-Liang- Shen-Lin-Fang- Wu- Zeng Based on conformal mapping of the complex variable function, the semi-infinite plane of a tunnel was transformed into a concentric ring region. With the soil around the tunnel regarded as a homogeneous, continuous,isotropic, saturated medium, the boundary collocation method was applied to control the local leakage of shield tunnels. The analytic method and numerical method were combined to solve the basic differential equation of the twodimensional seepage of saturated soil masses under steady seepage, and a semi-numerical and semi-analytical solution of pore water pressure variations due to local water leakage of shield tunnels is obtained. The effects of the water leakage range, location, and total water head difference between the ground surface and the tunnel leakage boundary on the pore water pressure of the soil mass around the tunnel are discussed through this calculation method. The results show that there are great changes to the pore water pressure under a one time central buried depth of a tunnel in the horizontal direction when lateral water leakage occurs, and the larger the leakage range, the more significant the decay rate of the pore water pressure; the larger the total water head difference between the ground sur? face and tunnel leakage boundary, the more obvious the influence is on the pore water pressure of the soil mass, and it is proportional to the total water head difference and volume of the pore water pressure reduction; and the lateral leakage volume of tunnels increases with an increase of the total water head difference, being characterized by a linear relationship. 2017 Vol. 54 (1): 89-95 [Abstract] ( 1142 ) [HTML 1KB] [ PDF 2095KB] ( 2032 ) 96 Control Values and Influence Factors of a Water Head of the Secondary Lining in a Bored Subway Tunne YANG Xiao-Ping- 1 Xu- Rao- 1 Liu-Ting-Jin- 1, 2 Wu-Shang-Yong- 1 Based on the features of secondary lining structures of bored subway tunnels in Guangzhou, the asymp? totic failure process of secondary linings under external water pressure was studied through three-dimensional numerical simulation, corresponding control values of the water head of each force stage were obtained, and sensitivity analysis was conducted for parameters affecting control values of the water heads. Based on the measured results at the site, an analytic demonstration was carried out regarding the main reasons for the local collapse of the secondary lining of a certain bored subway tunnel. The results show that: 1) the water head of a secondary lining of a common single line bored tunnel of Guangzhou metro is 30 m under initial cracking; 2) cracking depth exceeds the thickness of the protective layer if the water head goes beyond 47 m; 3) concrete is crushed if the water head is more than 90m; 4) the reinforcement yields if the water head is larger than 90 m and the crack cuts through the section if the water head is larger than 95 m; 5) the control value of the water head should be set to 47 m to guarantee the durability of the secondary lining; 6) the control values could be improved effectively with reasonable reinforcement and thickness of the secondary lining; and 7) the main cause for local collapse of the secondary lining of a certain bored subway tunnel is insufficient thickness of the secondary lining under high external water pressure. 2017 Vol. 54 (1): 96-104 [Abstract] ( 1202 ) [HTML 1KB] [ PDF 2359KB] ( 2090 ) 105 Deformation Prediction for Tunnel Surrounding Rock Based on the NonHomogeneous Exponential Function GM (1, 1) Model WANG Xin-Sheng- 1 Zuo-Wei-Qin- 2 Zhou-Cheng-Tao- 1 Chen- Yu- 1 Hou-Ya-Bin- 1 Considering that accuracy in measuring and predicting the rock deformation featured by time-varying in? crease and randomness is a key measure for ensuring the safety of tunnel construction, this paper predicts the rock deformations under three models, i.e., a conventional GM (1,1) model, a homogeneous exponential function GM (1,1)model and a non-homogeneous exponential function GM (1,1) model, and makes a relevant comparison. The results show that: the errors under the three models are 7.16%, 5.01% and 2.99%, respectively, while the relative errors are -8%, -5.52% and -3.05%, respectively, indicating that the non-homogeneous exponential function GM (1, 1)model is highly accurate for deformation prediction 2017 Vol. 54 (1): 105-109 [Abstract] ( 1178 ) [HTML 1KB] [ PDF 787KB] ( 1905 ) 110 On Characteristics of Displacements Induced by Approaching Metro Tunnel Construction in a Cobble Stratum LIANG Xiao-Yong- Jin- Jing- Zhang-Chun-Hui Taking a running tunnel approaching an existing railway bridge as an example, the characteristics of dis? placements induced by metro tunnel construction approaching an existing railway bridge are studied using the Hardening-Soil constitutive model, which compares 3D numerical calculations and site measured results. The following conclusions are made: 1) the rock of a cobble stratum is relatively loose and has poor cementation and stability of the rock mass, and the Hardening-Soil model may be used to simulate the stress-strain relation; 2) vertical displacement induced by running tunnel excavation is mainly concentrated at the tunnel crown and decreases gradually with the increasing of the overburden; 3) surface subsidence induced by the tunnel excavation may be regarded as the superposition of the surface settlement curves of two single-bore tunnels, and the measured values are consistant with the calculated values; 4) the maximum deformations of the existing railway bridge are smaller than the allowable displacements specified in“Railway Line Repair Rules,”and the existing excavation method and support parameters meet the operating conditions for the existing structure regarding its safety; 5) generally the excavation-induced horizontal displacement of the stratum and existing bridge structure is small; and 6) the running tunnel excavation-induced soil disturbance is mainly within the range of 5.4 m around the tunnel. 2017 Vol. 54 (1): 110-115 [Abstract] ( 1221 ) [HTML 1KB] [ PDF 2189KB] ( 1989 ) 116 Dynamic Simulation of the Effects of Design Parameters of Overlapped Tunnels on the Stability of Existing Tunnels WANG Hui- 1 Zhao-Wen-Juan- 2 Regarding construction of a new tunnel underneath an existing one, reasonable spacing and crossing an? gle are the important design parameters that affect stability. To study the influence of different spacings and crossing angles on an existing tunnel, a parametric model was set up that simulates the dynamic changes of spacing and crossing angle based on the ABAQUS platform and programming with Python language, and the influence of different spacings and crossing angles on deformations at key points of the existing tunnel were analyzed. A finite element optimization analysis and calculaton program was compiled based on Matlab language, and a calculation for a dynamic model was conducted by taking the minimization of deformation at key points of the existing tunnel as the optimization goal, then an optimal combination of spacing and crossing angle suitable for the tunnel was put forward.Through a comparison between optimization calculation results and field monitoring data, the validity of the calculation results was verified. This research enriches the simulation calculation method for studying the influence of overlapped tunnel construction. 2017 Vol. 54 (1): 116-122 [Abstract] ( 1175 ) [HTML 1KB] [ PDF 2726KB] ( 2019 ) 123 Numerical Analysis of Post-Construction Subway Settlement and Variation of Pore Pressures under the Influence of Construction Disturbance CHEN Kai- 1, 2 Ding- Zhi- 2 Gu-Xiao-Wei- 3 Wei-Xin-Jiang- 2 Ge-Guo-Bao- 2 At present, the subsoil deformation and pore pressure variation caused by metro construction have re? ceived extensive attention. Based on the Henkel pore pressure theory under three-dimensional stress conditions, the initial excess pore pressure at a tunnel spring line was obtained. The post-construction consolidation of the Hangzhou metro was simulated through the establishment of a three-dimensional finite-element model by MIDAS-GTS,and the subsoil settlement and distribution of the pore pressure at different time periods due to construction disturbance was analyzed. The results show that: the distribution of excess pore pressure is symmetrical and its dissipation is consistent with the subsoil consolidation degree after construction; consolidation settlement mainly occurs at the beginning of shield tunnelling and reaches a maximum at the ground; and the variation of pore pressure caused by metro operation decreases with an increase of the consolidation degree. 2017 Vol. 54 (1): 123-129 [Abstract] ( 1170 ) [HTML 1KB] [ PDF 2796KB] ( 2113 ) 130 Research on the Reserved Deformations of Unsymmetrical Loading Loess Tunnels with Different Slopes JIN Mei-Hai- 1, 2 Li-Dong-Liang- 1, 2 Liu-Xin-Rong- 1, 2 Liu-Feng-Ming- 3 Because of the unique physical and mechanical properties of loess and the unique asymmetrical force of unsymmetrical loading tunnels, the reserved deformations of a shallow-buried unsymmetrical loading tunnel in loess are different from a common tunnel. Based on the Sunjiagou tunnel in Shanxi province, field monitoring data are collected and analyzed using regression analysis by the least square method and a numerical simulation verification is conducted using the finite- element software ANSYS. The law of surrounding rock deformation varying with the slope of a shallow-buried unsymmetrical loading tunnel in loess is summarized. The research shows that the recommended reserved deformations are 10~15 cm for the shallow side of a shallow-buried double-tube tunnel in loess with a slope of 15° ~45° and surrounding rock of grade V, and the recommended reserved deformations are 20~25cm, 25~30 cm and 28~33 cm, respectively, for the deep side under the slopes around 15°, 30°and 45 °. 2017 Vol. 54 (1): 130-137 [Abstract] ( 1209 ) [HTML 1KB] [ PDF 3129KB] ( 2107 ) 138 Numerical Study of Crack Development of Shield Tunnel Lining Segments LAI Jin-Xing- 1, 4 Qiu-Jun-Ling- 1, 4 Liu- Chi- 1, 2 Pan-Yun-Peng- 3 Hu- Zhao- 1, 4 Segment cracks can affect the performance of shield tunnel linings. Based on tunnel segment cracking caused by a water inflow event in a certain running tunnel of the Xi′an metro, a three-dimensional nonlinear model was set up using ANSYS software SOLD65 element to analyze the crack development of tunnel segments. The results show that: 1) no cracks appear on the tunnel segment when the load is less than 2 times of the design value with the condition of no void; 2) the number of cracks gradually increases when the load is between 2.5 times and 4times the design value; 3) the relationship between the number of cracks and the load is close to a S-curve; 4) with the condition of voids, bias pressure appears when the designed load is applied, and segment cracks develop rapidly with an increase of the loading; 5) the number of cracks increases dramatically when the applied load is 2.7 times the designed load; 6) the crack distribution is asymmetrical and it is intensive near the voids; and 7) the structure is instable and failed when the applied load is more than 3 times the designed value. 2017 Vol. 54 (1): 138-144 [Abstract] ( 1216 ) [HTML 1KB] [ PDF 3491KB] ( 2031 ) 145 Displacement-Stress Based Multi-Information Intelligent Back Analysis in Highway Tunnels JIANG Zong-Bin- 1 Jiang-An-Nan- 1 Hu-Xue-Feng- 2 Liu-Yi-He- 2 Chen- Wei- 2 Liu-Gui-You- 2 Considering the limitation of the single controlling condition of displacement inversion, a multi-informa? tion based intelligent back- analysis method is presented, which combines an automatic acquisition system with three-dimensional numerical simulation to perform real-time monitoring, feedback and analysis of tunnel construction based on the advantages of fewer control variables, rapid convergence and strong adaptability of difference evolution algorithm (DE). Taking the Fusong tunnel as an example, sensors are set at section ZK276+354 to collect displacement information during construction at the measuring points considering the geological conditions and construction design. Using that data, a complex 3D numerical model is established, 25 sets of orthogonal schemes are designed to conduct forward calculations, a regression model is set up to show the relationship among various parameters of the rock mass and displacement and stress using range analysis and the fitting method, displacement-stress back analysis is carried out based on sensor data and routine monitoring data and accurate mechanical parameters of the surrounding rock are obtained. 2017 Vol. 54 (1): 145-152 [Abstract] ( 1111 ) [HTML 1KB] [ PDF 3085KB] ( 1890 ) 153 Development and Application of an Information Management System for Monitoring Subway Construction Safety Based on SuperMap Objects LI Yuan-Hai- 1, 2 Yang- Fan- 1, 2 Liu-Ji-Qiang- 3 Peng- Hui- 4 Li-Jian-Hua- 5 Efficient monitoring information management plays an important role in risk control during subway con? struction. Based on the SuperMap Objects of a domestic GIS component, a monitoring information management system for subway construction safety, which features an electronic map, a data set implying engineering information and an expression of mileage information, was developed with the Beijing underground transit line used as a background. This system integrates electronic mapping, editing and remote real-time monitoring; gives a general framework and rapid construction method and process of information management system for the safety monitoring of underground works; and has been promoted and applied in metro and highway tunnel projects in Beijing, Tianjin and Shenzhen. Practice shows that this SuperMap Objects based safety monitoring information management system has great practical value and good application prospects. 2017 Vol. 54 (1): 153-159 [Abstract] ( 1247 ) [HTML 1KB] [ PDF 2587KB] ( 1983 ) 160 A Study on Web-Based Tunnel Construction Risk Visualizations FU Xue-Wen- 1 Xue-Ya-Dong- 2, 3 Li-Yan-Jie- 2, 3 Such accidents as collapses occur from time to time due to inexhaustive geological surveying and im? proper construction management during tunnel construction, which cause severe threats to the safety of construction workers. A tunnelling collapse prediction model is developed based on the Bayesian Network and database with cases and experts′experiences, allowing the displacement and displacement rate to be set by taking the quantitative tunnel risk probability as the criterion. A Web-based risk visualization system for tunnel construction is put forward, realizing real-time monitoring, deformation prediction and risk warning visualizations for tunnel construction safety.Its application in a practical case indicates the proposed method and system can effectively provide warnings for the project. 2017 Vol. 54 (1): 160-167 [Abstract] ( 1190 ) [HTML 1KB] [ PDF 3336KB] ( 2243 ) 168 Element Joint Stiffness Properties of Large Immersed Tube Tunnels JIANG Zhi-Wei- 1 Bai- Yun- 2 Su-Quan-Ke- 3 Element joints of immersed tube tunnels play important roles during tunnel operation, and they can ad? just mechanical behavior and adapt to uneven deformation of a tunnel. A 3-D nonlinear finite-element model is established to analyze the mechanical properties of the element joints used in the Hong Kong-Zhuhai-Macao (HZM)immersed tube tunnel. This paper studies the relationship of axial compression stiffness, bending stiffness and axial compressive loading, compressive bending moment. The results indicate that axial compression stiffness increases with an increase of the axial compression load; and axial bending stiffness increases with an increase of the axial loading, while bending stiffness decreases with an increase of the bending moment under the same axial compression load. In addition, a model test is conducted to study the variation rule and influence factors of axial compression stiffness and bending stiffness of element joints. The results of the model test are compared with those by the finite-element method, and the variation rule of axial compression stiffness and bending stiffness agrees well with those of the FEM results. 2017 Vol. 54 (1): 168-174 [Abstract] ( 1194 ) [HTML 1KB] [ PDF 2502KB] ( 2099 ) 175 Analysis of the Causes and Treatment Measures for a Collapse in the Shangpingge Tunnel PENG Ze-Yu- 1, 2 Liu-Zuo-Qiu- 2 Regarding a collapse event in the Shangpingge tunnel in Fujian province, corresponding treatment mea? sures were proposed based on an analysis of the causes, and the strengh of the primary and secondary lining were verified after alteration using the load- structure method. It was concluded that unfavorable geological conditions,bad construction quality and an unsuitable excavation method are the major reasons for the tunnel collapse; a large bending moment of the primary and secondary lining occurs at the tunnel crown, haunch, arch foot and invert under the effect of the collapse load, and special attention should be paid to these postions during tunnel construction; and the minimum safety factor is 1.93 for dangerous cross-sections of the primary support and 2.43 for the secodary lining, which are larger than the values specified by the natioanl tunnel code, therefore meeting the requriements of engineering safety. 2017 Vol. 54 (1): 175-179 [Abstract] ( 1046 ) [HTML 1KB] [ PDF 2246KB] ( 1866 ) 180 Timely Grouting with Forms at the Crown of a Railway Tunnel Via a Lining Trolley GONG Cheng-Ming- 1 Zhu-Jia-Bin- 2 She-Hai-Long- 2 This paper briefly introduces the conventional treatment method for and prevention of the defects of voids at the tunnel crown, and focuses mainly on timely grouting with lining forms and embedded RPC pipe at the crown by a lining trolley. With this technology the problems of a hollow cavity, void and uncompacted concrete are solved and the integrity of the grouting material and lining are improved after being verified by radar scanning, thereby guaranteeing the safety of the structure. 2017 Vol. 54 (1): 180-185 [Abstract] ( 1245 ) [HTML 1KB] [ PDF 3861KB] ( 1780 ) 186 Research on the Treatment of Tunnel Mud Bursting at a Fault Zone ZHANG Hui-Ling- Fan-Sheng-Ming The Tuanshan No.1 fault of the Nanchong tunnel, which is mainly made up of fault rubble, is an active holocene fault. During tunnel construction, serious surface subsidence and mud burst happened. This paper introduces the whole event process and presents corresponding measures in detail, such as backfilling at surface collapsed cavity, phased sludge cleaning inside the tunnel, and grouting consolidation with sulphate aluminium cement. 2017 Vol. 54 (1): 186-190 [Abstract] ( 1124 ) [HTML 1KB] [ PDF 1892KB] ( 2346 ) 191 Analysis of the Causes and Treatment Measures for a Collapse in the Shangpingge Tunnel GAO Deng Regarding a collapse event in the Shangpingge tunnel in Fujian province, corresponding treatment mea? sures were proposed based on an analysis of the causes, and the strengh of the primary and secondary lining were verified after alteration using the load- structure method. It was concluded that unfavorable geological conditions,bad construction quality and an unsuitable excavation method are the major reasons for the tunnel collapse; a large bending moment of the primary and secondary lining occurs at the tunnel crown, haunch, arch foot and invert under the effect of the collapse load, and special attention should be paid to these postions during tunnel construction; and the minimum safety factor is 1.93 for dangerous cross-sections of the primary support and 2.43 for the secodary lining, which are larger than the values specified by the natioanl tunnel code, therefore meeting the requriements of engineering safety 2017 Vol. 54 (1): 191-197 [Abstract] ( 1186 ) [HTML 1KB] [ PDF 2622KB] ( 2071 ) 198 Comprehensive Technology for Shields Arriving Under Complicated Conditions TIAN Hai-Bo Based on the design practice of subway engineering, this paper summarizes the design schemes for shield arrival shaft combined with the mined station. Through a comprehensive consideration of factors such as shield hoisting, air duct construction, running tunnel construction, station construction, air duct layout, etc., this paper analyzes the advantages and disadvantages of various schemes and their adaptabilities. Additionally, a scheme is recommended for hoisting a shield out of a shaft by making use of the mined underground shaft, air duct and air shaft considering that it is not possible to set up a separate shaft around a mined station. Through design calculation,the design technology for a large shaft is summarized. The results show that traffic condition, construction period and station form are the main influencing factors for setting a shield arrval shaft, and it is feasible to construct a shield arrival shaft in combination with a station air duct. 2017 Vol. 54 (1): 198-203 [Abstract] ( 1144 ) [HTML 1KB] [ PDF 3660KB] ( 2254 ) 204 Key Techniques for Semi-Open Shield Tunnelling in Upper-Soft Lower-Hard Strata LI Zeng-Li- Wang- Wei Considering that upper-soft lower-hard strata may increase construction risks and cause ground settle? ment during shield tunnelling, and using the unhomogeneous strata in Nanjing as an example, this paper analyzes the stability of the working face and relevant construction parameters during tunnelling, and then proposes suitable tunnelling modes and auxiliary measures. 2017 Vol. 54 (1): 204-208 [Abstract] ( 1139 ) [HTML 1KB] [ PDF 1533KB] ( 2249 )

More>>   · · More>>

Copyright © 2011  Editorial By MODERN TUNNELLING TECHNOLOGY Supported by:Beijing Magtech Co.ltd  Email:support@magtech.com.cn