Given the difficulties encountered in roadway support under coal pillars,we studied the characteristics of stress distribution and their effect on roadway stability,using theoretical analysis and numerical simulation....Given the difficulties encountered in roadway support under coal pillars,we studied the characteristics of stress distribution and their effect on roadway stability,using theoretical analysis and numerical simulation.The results show that,under a coal pillar,vertical stress in a floor stratum increases while horizontal stress decreases.We conclude that the increased difference between vertical and horizontal stress is an important reason for deformation of the surrounding rock and failures of roadways under coal pillars.Based on this,we propose control technologies of the surrounding rock of a roadway under a coal pillar,such as high strength and high pre-stressed bolt support,cable reinforcement support single hydraulic prop with beam support and reinforcement by grouting of the surrounding rock,which have been successfully applied in a stability control project of a roadway under a coal pillar.展开更多
The movement principle of sidewalls and floor of extraction opening is analyzed, it is found that floor heave not only has something to do with the floor strata, but sidewalls. The effect of sidewall anchor and corner...The movement principle of sidewalls and floor of extraction opening is analyzed, it is found that floor heave not only has something to do with the floor strata, but sidewalls. The effect of sidewall anchor and corner anchor is studied, the mechanical principle of reinforcing sidewalls and corners is put forward and applied in engineering practice.展开更多
Coal roadway support is the foundation and strong guarantee of safe coal production. With the FLAC3D numerical simulation, the roadway fulllength anchor support mechanism was studied, and the full-length anchor forcet...Coal roadway support is the foundation and strong guarantee of safe coal production. With the FLAC3D numerical simulation, the roadway fulllength anchor support mechanism was studied, and the full-length anchor forcetransferring mechanism and stressfield distribution formed by roadway surrounding rocks were analyzed, which will provide a scientific basis for a support technology in large-section roadways under complicated geological conditions and lay a foundation for the popularization and application of a full-length anchor support system under special geological conditions.展开更多
This paper presents a design concept and acceptance test application procedure for a deep pit protection structure. The structure is intended for use in the construction of three underground levels of a residential bu...This paper presents a design concept and acceptance test application procedure for a deep pit protection structure. The structure is intended for use in the construction of three underground levels of a residential building: A, B, C and D, located in Block 10C, Budva, Montenegro. The anchored wall will consist of non-gravity cantilevered walls with three levels of ground anchors. Non-gravity cantilevered walls employ continuous walls constructed in slurry trenches (i.e., slurry (diaphragm) walls), e.g., vertical elements that are drilled to depths below the finished excavation grade. For those non-gravity cantilevered walls, support is provided through the shear and bending stiffness of the vertical wall elements and passive resistance from the soil below the finished excavation grade. Anchored wall support relies on these components as well as lateral resistance provided by the ground anchors to resist horizontal pressures (e.g., earth, water and external loads) acting on the wall. The anchored wall analyzed in this paper will be recommended for use as a temporary supporting structure necessary for the excavation and erection of the underground structure. The design life of the temporary ground anchors is two years. Dynamic loads are not considered in this analysis.展开更多
The designing method and the supporting mechanism of both bolt and small cable anchor for full seam roadway in the weaker thick coal seam are systematically analyzed, and the construction technology and the supporting...The designing method and the supporting mechanism of both bolt and small cable anchor for full seam roadway in the weaker thick coal seam are systematically analyzed, and the construction technology and the supporting results are briefly summarized.展开更多
基金the National Natural Science Foundation of China(No.50774077)the State Key Laboratory of Coal Resources and Safe Mining Autonomous Study Subject Foundation of China(No.SKLCRSM08X04)+2 种基金the National Basic Research Program of China,the National Excellence Doctor Degree Dissertation Special Foundation of China(No.200760)the New Century Talent Support Program of the Ministry of Education of China(No.NCET-06-0475)the Youth Scientific Research Foundation of China University of Mining & Technology(No. 2008A002)
文摘Given the difficulties encountered in roadway support under coal pillars,we studied the characteristics of stress distribution and their effect on roadway stability,using theoretical analysis and numerical simulation.The results show that,under a coal pillar,vertical stress in a floor stratum increases while horizontal stress decreases.We conclude that the increased difference between vertical and horizontal stress is an important reason for deformation of the surrounding rock and failures of roadways under coal pillars.Based on this,we propose control technologies of the surrounding rock of a roadway under a coal pillar,such as high strength and high pre-stressed bolt support,cable reinforcement support single hydraulic prop with beam support and reinforcement by grouting of the surrounding rock,which have been successfully applied in a stability control project of a roadway under a coal pillar.
文摘The movement principle of sidewalls and floor of extraction opening is analyzed, it is found that floor heave not only has something to do with the floor strata, but sidewalls. The effect of sidewall anchor and corner anchor is studied, the mechanical principle of reinforcing sidewalls and corners is put forward and applied in engineering practice.
基金Supported bythe National Natural Science Foundation of China (50904024) the State Key Laboratory Research Fund of Coal Resources and Mine Safety of China University of Mining & Technology (10KF02) the Doctoral Fund of Henan Polytechnic University (B2009-66)
文摘Coal roadway support is the foundation and strong guarantee of safe coal production. With the FLAC3D numerical simulation, the roadway fulllength anchor support mechanism was studied, and the full-length anchor forcetransferring mechanism and stressfield distribution formed by roadway surrounding rocks were analyzed, which will provide a scientific basis for a support technology in large-section roadways under complicated geological conditions and lay a foundation for the popularization and application of a full-length anchor support system under special geological conditions.
文摘This paper presents a design concept and acceptance test application procedure for a deep pit protection structure. The structure is intended for use in the construction of three underground levels of a residential building: A, B, C and D, located in Block 10C, Budva, Montenegro. The anchored wall will consist of non-gravity cantilevered walls with three levels of ground anchors. Non-gravity cantilevered walls employ continuous walls constructed in slurry trenches (i.e., slurry (diaphragm) walls), e.g., vertical elements that are drilled to depths below the finished excavation grade. For those non-gravity cantilevered walls, support is provided through the shear and bending stiffness of the vertical wall elements and passive resistance from the soil below the finished excavation grade. Anchored wall support relies on these components as well as lateral resistance provided by the ground anchors to resist horizontal pressures (e.g., earth, water and external loads) acting on the wall. The anchored wall analyzed in this paper will be recommended for use as a temporary supporting structure necessary for the excavation and erection of the underground structure. The design life of the temporary ground anchors is two years. Dynamic loads are not considered in this analysis.
文摘The designing method and the supporting mechanism of both bolt and small cable anchor for full seam roadway in the weaker thick coal seam are systematically analyzed, and the construction technology and the supporting results are briefly summarized.