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Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hazard Control in Tunnelling & Underground Engineering is the property of Shandong University Scientific Journals Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Relying on the actual engineering case of grouting water plugging in water-rich fractured rock of Qingdao Metro, the field test of the applicability of grouting materials was carried out. The applicability of regular cement slurry, cement-sodium silicate slurry, and superfine cement slurry under the water yield standard requirements of two inspection holes, 0.2 L.min-1, m-1 and 0.01 Lmin-1 m-1, was studied. Suggestions for water plugging grouting materials in water- rich fractured rock that match the requirements of different standards were proposed. The applicability of the grouting material was verified by means of Borehole TV and actual excavation verification. Research indicated： it was difficult to meet the requirements of waterless operation by using regular cement slurry alone (the water yield from the borehole was less than 0.01 Lmin-1 m-1), but after repeated grouting, the water yield from the borehole could meet the requirement of no more than 0.2 L min-1 m-1. Cement-sodium silicate slurries had a short gel time, which could effectively limit the diffusion scope of the slurry. By coordination application of regular cement slurry and cement-sodium silicate slurry, the grouting effect was significantly better than regular cement single-liquid slurry; The superfine cement slurry had low particle size, which could effectively fill the micro-fracture space in the water-rich fractured rock and improve the water plugging efficiency of the tunnel surrounding rock. The use of regular cement slurry, cement-sodium silicate slurry and superfine cement slurry to carry out advanced curtain grouting of water-rich fractured rock could meet the requirements of tunnels waterless operation. The research results could provide a basis for the treatment design of grouting and field construction in water-rich fractured rock. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Advanced Engineering Science / Gongcheng Kexue Yu Jishu is the property of Advanced Engineering Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Permeation grouting method is effectively used in sand layer which usually exposed by mine shaft to shutoff water and reinforce strata. To study the permeation grouting reinforcement effect of sand layer, a simulation test device was developed for testing permeation grouting, which can grout several samples simultaneously and measure permeability coefficient without mold stripping. Compressive strength, deformation modulus and permeability coefficient were used as the evaluation index of grouting reinforcement effect. With four influencing factors, including sand layer gradation, cohesive soil content, water cement ratio and grouting pressure, the or-thogonal test of permeation grouting reinforcement effect was implemented. Ultimately, the main controlling factor of grouting reinforcement effect was obtained, andthe deformation and failure characteristics of grouted sand samples under different conditions were revealed. Results show that: sand layer obtains better performances after grouting, three day compressive strength reaches 0. 5-8. 5 MPa, three day deformation modulus reaches 35-750 MPa, and one day permeability coefficient reaches 10-6～10-7 cm/s. Water cement ratio of slurry is the main con-trolling factor of permeation grouting reinforcement effect of sand layer. When water cement ratio grows, the compressive strength, deformation modulus and anti-permeability of sand layer will decrease significantly. De-formation and failure mode of grouted sand is affected by water cement ratio markedly. Low water cement ratio (W/C = 0.8) will lead to global failure mode. High water cement ratio (W/C = 1.6) will result in local deformation and failure mode, and the bleeding water effect of cement will affect the failure process of grouted sand. First selection of cement grout with low water cement ratio is suggested in the permeation grouting projects of sand layer. [ABSTRACT FROM AUTHOR]

Coal mining in the aquifer with high bearing pressure often needs to carry out the transformation to the strong aquifer.Tens of thousands of tons of grouting material are used because of the large scale of aquifer.Based on the modification mechanism of inorganic composite,a new type of inorganic grouting material is developed by using solid waste in mine and thermal power plant.The optimum mixture ratio of new material system is obtained by the laboratory test.The flexural strength,compressive strength,permeability coefficient of different composi-tions are tested,combining with the grouting engineering to select ratio.The microscopic structural performance of grouting stone body is tested by the micro analysis means of XRD and SEM.The mechanical properties,economic factors and environmental benefits are compared,and the applicability of the new materials and conventional grouting materials is compared.The results show that the cement content is 35%,the early strength and later strength of the new grouting material are higher than that of the cement clay slurry at the same time when the cement content is 40%.The cement content is 30%,the clay content is 10%,the coal gangue content is 60%,with appropriate content water reducing agent and accelerator.As for composite material stone body (28 d),the com-pression strength is 3.4 MPa,the flexural strength is 1.7 MPa,and the permeability coefficient is 1.794×10-7 m/s.The results meet the requirements of aquifer grouting reconstruction,which is expected to offer some reference to similar projects. [ABSTRACT FROM AUTHOR]