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Fu J.-W.,North China University of Water Conservancy and Electric Power | Chen K.,State Key Laboratory of Shield Machine and Boring Technology | Zhu W.-S.,Shandong University | Zhang X.-Z.,North China University of Water Conservancy and Electric Power | Li X.-J.,Shandong Jianzhu University
Engineering Fracture Mechanics | Year: 2016

A new rock-like resin has been developed after extensive formula research. This resin is completely transparent and low temperature brittle. Its tension-compression ratio can reach 1/6.6 in the −10 to −15 °C temperature range. It can simulate many kinds of engineering rocks. Specimens are made with a single internal crack. The progressive failure processes of specimens under uniaxial and biaxial compressions are investigated. The uniaxial failure process of specimens is divided into four stages. Some forms of secondary cracks, like anti-wing cracks in biaxial test, have never been reported in previous studies. 3-D numerical simulation is carried out using FLAC3D. A new elastic-brittle constitutive model is developed in the simulation. Superfine element division is also required. The uniaxial and biaxial numerical results of the new method possess an excellent consistency with experiment results in this paper. © 2016 Elsevier Ltd


Zhang X.,CAS Institute of Geology and Geophysics | Wang S.,CAS Institute of Geology and Geophysics | Han G.,CAS Institute of Geology and Geophysics | Zhang B.,State Key Laboratory of Shield Machine and Boring Technology
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2011

To study the progressive failure of schistose rock, three stress thresholds, i.e. crack initiation stress σci, crack damage stress σcd and uniaxial compression peak strength σf, and their relationship between each other are summarized and discussed systematically. Based on the uniaxial compression axial stress-axial/radial strain curves of Danba quartz mica schist, analysis of stress thresholds of schistose rock in progressive failure process are firstly applied to schistose rock. Stress thresholds under the three conditions of schistose foliation oriented perpendicular, parallel, and at 30° to loading direction respectively are obtained, which are compared with those of other sorts of rock in references. Results show that the crack propagation are related to rock type. Grain size of mineral, cement bond quality between mineral grains and schistose and joint plane development are all the factors to influence the progressive failure process of rock. Different stress threshold ranges of different types of rock are then got accordingly. Experimental research results of quartz mica schist indicate that due to the joint plane developments, strong anisotropy exists in the schistose rock crack propagation under uniaxial compression. This distinguishing characteristics should be considered quantitatively during underground excavation and support design.


Chen K.,Tianjin University | Chen K.,State Key Laboratory of Shield Machine and Boring Technology | Feng H.,State Key Laboratory of Shield Machine and Boring Technology
Modern Tunnelling Technology | Year: 2014

With the rapid development of urban construction, the construction of rail-and-road combined tunnels is getting to be an effective way to realize efficient utilization of underground space. Based on the construction conditions of the Sanyang river-crossing tunnel in Wuhan, this paper proposes a construction scheme for the rail-and-road combined tunnel with six lanes based on a comprehensive comparison and analysis of the influences of urban planning and land use, construction difficulties, and construction organization. It describes the relevant calculations and analyses regarding the cross-section arrangement and tunnel structure, etc. Additionally, it discusses a feasibility study of technical difficulties such as equipment manufacturing, long-distance driving, constructing with a small clearance, and adjacent construction, and ultimately provides guidance for this project and similar ones in the future.


Feng H.,State Key Laboratory of Shield Machine and Boring Technology | Chen K.,State Key Laboratory of Shield Machine and Boring Technology | Zhou J.,State Key Laboratory of Shield Machine and Boring Technology | Li F.,State Key Laboratory of Shield Machine and Boring Technology | Wang Z.,State Key Laboratory of Shield Machine and Boring Technology
Modern Tunnelling Technology | Year: 2014

To further improve the rock-breaking performance of TBM cutters, it is particularly important to determine proper cutter spacing during the cutter design process. In this paper, based on a cutter spacing range derived from the rock crushing angle, an analysis of rock-breaking performance under double and triple cutters with different cutter spacings was carried out in accordance with the RFPA analytic system, and a calculation formula for optimum cutter spacing was deduced. Then, the self-developed comprehensive test platform was used to test rock-breaking performance during the sequential rolling of three cutters with different cutter spacings to verify the accuracy of this formula. The derived calculation formula for optimum cutter spacing was proven to be scientific by the test results, and the effective rock-breaking theory for cutters was further improved.


Feng H.-H.,State Key Laboratory of Shield Machine and Boring Technology | Chen K.,State Key Laboratory of Shield Machine and Boring Technology
Journal of Railway Engineering Society | Year: 2016

Research purposes: West Qinling Tunnel of Lanzhou-Chongqing Railway has some characteristics of long lines, high construction difficult and new construction technology, whose total length is about 28.23 km. In order to better solve the difficult problems of disassembled scheme in-tunnel of West Qinling Tunnel, in view of the drawback to research on TBM disassembled technology in-tunnel, the key technologies were fully researched and analyzed from the two aspects of TBM disassembled preparation scheme and system demount methods, providing reference for this and similar project construction. Research conclusions: (1) When the scheme of TBM disassembled in-tunnel was designed, we should take full account of demount chamber design, construction equipment configuration, facilities cleaning and step mechanism installation. (2) The work of host section disassembly was in strict accordance with the order of 1# bridge, support system, shield, cutterhead, main bearing and mounting rack. (3) Identification methods of mechanical components, electric system and hydraulic system were summarized. (4) Width of demount chamber is smaller than actual demand, 0.5 meter of allowance need to be increased per side. After the disassembly cleaning of cutterhead was completed, a comprehensive inspection was taken, and the special schemes for the maintenance and storage of main bearing were formulated. (5) The research results can provide guidance for TBM disassembled in-tunnel of this and similar projects in the future, to ensure construction safety and high efficiency. © 2016, Editorial Department of Journal of Railway Engineering Society. All right reserved.


Chen K.,Tianjin University | Chen K.,State Key Laboratory of Shield Machine and Boring Technology | Feng H.,State Key Laboratory of Shield Machine and Boring Technology
Modern Tunnelling Technology | Year: 2015

Due to the requirement of higher running speeds, large-diameter shield tunnelling is a trend for future urban metro tunnels, and the φ6.98 m large-diameter EPB shield was first used in the construction of Shenzhen Metro line 11. This paper examines the construction difficuilties in Lot 11301 of Shenzhen Metro line 11, such as driving in spheroidal weathered granite, shield attitude control in heterogeneous soft ground and mud caking at the cutterhead due to soft clay, and proposes a specific adaptability design in terms of the main drive configuration, cutting tools, shield body, screw conveyer and muck conditioning system. Furthermore, suggestions are presented for optimization of the large-diameter shield. ©, 2015, Editorial Office of "Modern Tunnelling Technology". All right reserved.


Chen K.,State Key Laboratory of Shield Machine and Boring Technology | Feng H.,State Key Laboratory of Shield Machine and Boring Technology
Energy Education Science and Technology Part A: Energy Science and Research | Year: 2014

For better experiment research on the shield cutter-head driving system, a simulator was designed. Based on the analysis of structure principle and functional characteristics, critical components of the simulator were designed and analyzed, such as, installing support, inertia load loading system, gear system with two inputs, and so on. From the research result of experiment on the simulator, the value of cutter rotating speed and maximum output torque can meet the requirements of 0-3r/min and 1956Nm separately. So, the simulator can meet requirement of research on shield cutter-head driving system. © Sila Science. All Rights Reserved.


Zhou J.,State Key Laboratory of Shield Machine and Boring Technology | Wang D.,Southwest Jiaotong University
Geotechnical Special Publication | Year: 2016

Based on a shield tunneling project using earth pressure balance (EPB) construction method in Tianjin, China, this paper builds a database of real monitored data which includes ground surface settlement at different phases of tunneling, chamber earth pressure, grouting pressure and volumes as well as excess pitch information. A model to determine the earth pressure in head chamber to maintain the face stability is proposed and verified with monitored data. Moreover, grouting volumes are analyzed and compared with different considerations. © ASCE.


Li X.,Zhejiang UniversityZhejiang | Zhang H.,State Key Laboratory of Shield Machine and Boring Technology | Xue Y.,Zhejiang UniversityZhejiang | Shao C.,Zhejiang UniversityZhejiang
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2015

The most important part of the excavation for slurry shield machine is keeping the earth pressure and slurry circulation system pressure in balance. In this paper, an excavating face pressure balance principle for direct type slurry shield machine is analyzed and the pressure balance dynamic model is introduced. Then, a controller is designed based on predictive function control method. Finally, the controller initialization method is proposed to deal with the problem of controller switching from manual to automatic mode. Simulation results show the improved performance of proposed method. © Springer International Publishing Switzerland 2015.


Lu Y.-F.,China Three Gorges University | Lu Y.-F.,Wuhan University | Lu T.,China Three Gorges University | Zhou J.-J.,State Key Laboratory of Shield Machine and Boring Technology | And 2 more authors.
Yantu Lixue/Rock and Soil Mechanics | Year: 2013

The classification as three types is proposed for the load-displacement relation curve of the rock-soil mass at first; a criterion of high earth pressure is defined. A new constitutive theory is at first proposed; the complete-process relation of stress-strain can be described under different normal stresses (or different confining pressures) by this theory. There only exist three mechanical parameters describing the geomaterial and stress state. It describes not only the mechanical behavior of geomaterial, but also of the complex material and of the surface between different media, the arbitrary deformation can be obtained. The relationship of stress-strain for the different rock-soil masses and the surface between rock-soil layer and pile are described by the proposed constitutive theory. The testing data of pile foundation of Changshawan bridge are simulated; the results show: that the mechanical properties of different rock-soil masses and interlayer between rock-soil mass and pile can be presented by this constitutive theory.

Loading State Key Laboratory of Shield Machine and Boring Technology collaborators
Loading State Key Laboratory of Shield Machine and Boring Technology collaborators