Tianjin Metro Group Co.

Tianjin, China

Tianjin Metro Group Co.

Tianjin, China
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Wang Y.,Shijiazhuang University | Bo H.,Tianjin Metro Group Co. | Yu B.,Shijiazhuang University
International Journal of Modelling, Identification and Control | Year: 2011

The core of the problem in urban rail transit braking is the ascertainment of the braking point and the calculation of the braking distance. In order to fix the position of the braking point when the train pulled in the station by using the simulation more accurately and rapidly, the regular braking method was improved through breaking the recursive algorithm which took time as the step length, and the new model, which can confirm the braking point and the braking distance based on the speed difference value calculated by the train running distance as the step length, is put forward in this paper. The new model solves the problems such as large calculation amount and slow computing speed in the conventional variable iteration, and it plays an active role in the traction calculation software upgrade of urban rail traffic and automatic unmanned train technology. Copyright © 2011 Inderscience Enterprises Ltd.


Yang Y.-Q.,The Third Railway Survey and Design Institute Group Corporation | Zhao J.,Tianjin Metro Group Co. | Yang G.-S.,The Third Railway Survey and Design Institute Group Corporation
Journal of Railway Engineering Society | Year: 2015

Research purposes: The subsea tunnel project in Taishan nuclear power station is the first subsea shield tunnel in China with external diameter 9 m through middle weathered rock, clay, sand and the interface of soil and rock. The geological and geotechnical condition in this tunnel is very complex. The main character of this project is large diameter shield tunnel, long distance construction in complex geological strata. The difficulties include tunneling construction method, longitudinal profile design, structure design, TBM selection and cutting head design, the treatment of tunneling through interface of soil and rock and boulders group. Through theory analysis and experience analogy, the safe and reasonable design scheme was demonstrated. Research conclusions:(1)The tunnel machine in this project adopt the mix-shield TBM, Shield tunneling method combines with New Austria Tunneling Method. The lining of the tunnel is combined type of universal segments lining and cast in concrete lining. It effectively solves the problem of long distance and under the sea tunneling. (2) The mix-shield cutter head design, boulders blast under the sea solves the problem of high risk and low efficiency speed of tunneling. (3)Through practice, it is demonstrated that this design can effectively solve the technical problems of subsea tunnel, and effectively control the construction risks, which can provide some references for the related projects and future channel tunnels construction. ©, 2015, Editorial Department of Journal of Railway Engineering Society. All right reserved.


Guo Y.-B.,Tianjin University | Guo Y.-B.,Zhengzhou Institute of Aeronautical Industry Management | Zhang L.-M.,Tianjin Metro Group Co. | Zheng G.,Tianjin University | Yang Z.-D.,Tianjin Metro Group Co.
Yantu Lixue/Rock and Soil Mechanics | Year: 2014

Shield tunneling passing through adjacent large interchange's super-long piles has negative effect on super-long piles and bridge structures. Numerical analysis is conducted to simulate the process of the shield tunneling passing through the adjacent super-long piles. The bearing performance, deformations and forces of super-long piles caused by the shield tunneling with different depths are investigated. Some conclusions are drawn as follows: large deformations and forces may occur in piles due to nearby tunneling. The various tunneling locations have different influences on the behaviors of piles. The most unfavorable position for lateral displacement is the upper part of pile; the most unfavorable position for longitudinal displacement is the middle part of pile; the most unfavorable position for vertical displacement is the tip of pile; the most unfavorable position for additional axial force is the lower part of pile, when other conditions are the same. The shaft resistances appear "S-shaped" distribution near the tunnel axis; meanwhile, the maximum axial forces of the piles are also located at the tunnel axis. Lateral and longitudinal deformations of piles that extend to bridge decks are considerable. Horizontal deformations of piles top should be strictly controlled while tunneling passing through adjacent interchange's super-long piles.


Zheng G.,Tianjin University | Du Y.-M.,Tianjin University | Diao Y.,Tianjin University | Deng X.,Tianjin Architecture Design Institute | And 2 more authors.
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2016

The unloading effect of excavations can cause deformation of the adjacent existing tunnels, which may seriously influence the operation and safety of the tunnels and hence should be strictly controlled. Based on the field measurements of a project in Tianjin and a large number of case histories, the finite element method considering the small strain of soil is adopted to conduct parametric studies on the relationship between the deformation of the existing tunnels and the excavation construction. According to various deformation controlling criteria for the existing tunnels, the retaining side of excavation is zoned with different deflection modes and maximum horizontal displacements of retaining structures. It is shown that the influenced zone can be simply characterized by a right trapezoid, which can be used to predict the deformation of the existing tunnels approximately according to the relative locations of the tunnels, deflection modes and maximum horizontal displacements of retaining structures. For a given deflection mode of the retaining structures and a deformation controlling criterion, the influenced zone expands as the maximum horizontal displacement of the retaining structure increases. Under the same criteria and maximum horizontal displacement of the retaining structures, the range of the influenced zone increases with the variation of deflection modes in the order of cantilever type, convex type, composite type and kick-in type. © 2016, Chinese Society of Civil Engineering. All right reserved.


Sun L.-Q.,Tianjin University | Lu J.-X.,Tianjin University | Li H.,HIGH-TECH | Yan S.-W.,Tianjin University | And 2 more authors.
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2015

The artificial freezing method is widely used in the urban construction of underground engineering, such as the foundation reinforcement and excavation of subway tunnels. The strength properties of artificially frozen soils are affected by many factors. Water content, temperature, salt content and other factors affect the strength of artificially frozen soils to a large degree. At present, a lot of researches on uniaxial compressive strength of artificially frozen soils has been made, but they are certainly regional. For the silty clay and clay in Tianjin area, a series of uniaxial compressive strength tests are conducted with different water and salt contents. According to the test results, the effects of water and salt contents on the strength characteristics and the "optimum water content of the artificially frozen soils" are obtained. The test results show that the dry density of the soils has little effect on the water content corresponding to the peak strength of silty clay and clay. The conclusions can be used to guide the design of engineering in Tianjin area. ©, 2015, Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering. All right reserved.


Sun L.-Q.,Tianjin Key Laboratory of Soft Soil Characteristics and Engineering Environment | Sun L.-Q.,Tianjin University | Ren Y.-X.,Tianjin University | Yan S.-W.,Tianjin University | And 2 more authors.
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2015

With the development of underground engineering, the artificial freezing method has become the common techniques of underground construction. The law of the development of artificial frozen temperature field and the influence on the surrounding environment because of frost heave in the freezing process need to be further studied. The law of variation of the thermal physical parameters along with the temperature field is obtained through laboratory tests, then a numerical method considering thermal stress coupling in the process of artificial freezing is proposed and established based on an artificial frozen soil project of a connecting passage of Tianjin subway. The development law of temperature fields and the amount of frost heaving of soil during freezing process are calculated by using this method. The proposed method is proved to be feasible by comparing the calculated results with the actual data. Consequently, the proposed method can provide guidance and reference for the design and construction of artificial freezing projects. ©, 2015, Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering. All right reserved.


Du Y.-M.,Tianjin University | Zheng G.,Tianjin University | Zhang L.-M.,Tianjin Metro Group Co.
Yantu Lixue/Rock and Soil Mechanics | Year: 2014

For the piles beneath deep excavations, the distribution of pile shaft resistance is different from that under conventional condition. Based on the field tests and numerical simulation of super-long bored piles, theoretical analysis is conducted to investigate the different settlement behaviors caused by the shaft resistance distributions under both conventional and excavation conditions. The results show that due to the low tip resistance of the super-long pile under working load, the comprehensive coefficients of pile compression depend on the distributions of shaft resistance. The comprehensive coefficients of pile compression recommended in the current code are reasonable for super-long bored pile under conventional condition. However, it is found that the comprehensive coefficient of pile compression under excavation condition is 20% larger than the recommended value in the current code. Therefore, the settlement of pile may be underestimated without considering excavation effect. Furthermore, for the pile under deep excavation condition, the comprehensive coefficient of pile compression decreases with the increase of the slenderness ratio l/d; while for the pile under conventional condition, there is no direct relation between the comprehensive coefficient of pile compression and the slenderness ration.


Xu Z.-M.,Tianjin University | Xu Z.-M.,Tianjin Metro Group Co. | Han Q.-H.,Tianjin University | Zheng G.,Tianjin University | Zhang L.-M.,Tianjin Metro Group Co.
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2013

Two historic buildings are subjected to the impact of nearby excavation and underlying tunneling, which has to be strictly controlled. Countermeasures include ground sleeve valve pipe grouting, top-down method of metro station excavation, diaphragm cut-off wall of confined water, freezing method outside the end well, and optimized parameters of shield tunneling. The settlements of the historic buildings induced by underlying tunneling, dewatering and excavation of nearby underground metro station, freezing and grouting outside end well are measured and analyzed. The field measured data show that the settlements of buildings can be minimized by applying the optimized shield tunneling parameters. Leakage during the construction of horizontal freezing hole and tunneling may cause significant settlement of overlying buildings. The building with large weight can hardly be lifted by grouting when there is soft clayey soil layer between building foundation and grouting. While the building with small weight can be lifted under such conditions. However, the rise of the building can be part offset by the consolidation of soft clayey soil due to the dissipation of the excessive pore water pressure generated during grouting. Freezing zone is vital to leakage prevention during tunneling in the freezing zone before the shield enters the end well. The effect must be evaluated, especially before the large jack force is adopted to advance the shield.


Liu F.,Tianjin Metro Group Co. | Xie X.,Tongji University
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2014

The settlement control of adjacent building is a critical issue in foundation pit construction. The impacts of the construction of both three-axis high-pressure rotary jet grouting piles and diaphragm wall on a historical building in a subway station of Tianjin were analyzed based on the real time monitoring data, focusing on the effect of trench construction of diaphragm wall on the adjacent building settlement. The settlements in the retaining structure construction phase, the foundation pit excavation phase and the whole construction period were compared, to explore the impacts of three-axis high-pressure rotary jet grouting piles retaining structure and diaphragm wall on the building settlement. The reasons for building settlement caused by different retaining structure forms were emphatically analyzed and settlement control methods were proposed for building protection. The results obtained could provide reference to similar projects.


Feng G.,Electronic Information Vocational Technology College | Sun S.J.,Tian Jin Metro Group Co.
Applied Mechanics and Materials | Year: 2014

In the past, the semi-active control study generally is calculated based on the MATLAB numerical procedure, which can't achieve fine simulation. In this paper, to solve this problem, the finite element software ABAQUS is taken to be secondary development, a numerical simulation method of studying semi-active control is proposed. And the seismic response of a steel column is taken for the research. the numerical simulation analysis of the semi-active control is carried out. The results show that the control effect of the control method is significant, and the simulation result is clearly visible. © (2014) Trans Tech Publications, Switzerland.

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