The front abutment pressure of a fully-mechanized workface of 11061 soft coal isolated island of Liangbei Coal Mine was measured and studied using a self-developed mining-induced stress monitoring system associated wi...The front abutment pressure of a fully-mechanized workface of 11061 soft coal isolated island of Liangbei Coal Mine was measured and studied using a self-developed mining-induced stress monitoring system associated with electromagnetic radiation technology, and the effects of abutment pressure distribution on strata behavior we discussed. The results indicate that the miningdnduced influencing distance advanced at the fully-mechanized working face of soft coal isolated island is larger than that at the gen- eral working face at the isolated island, besides the fracture zone in front of working face was widened to some extent, and the influencing range caused by relaxations on both roadways became bigger with the advancing working face. Moreover, it can be indicated that mining has significant effect on strata behav- ior of fully-mechanized working face of soft coal isolated island, which is mostly distributed in the area of stress concentration. The research results have an important reference value for revealing the distribution pattern of the front abutment pressure of a fully-mechanized working face of soft coal isolated island, and controlling the coal-rock dynamic disaster occurrence under similar mining conditions.展开更多
Based on the engineering project on a small coal pillar of 12,521 working face roadway in Xieqiao Coalmine, data regarding surface displacements of the coal pillar, deep displacements and mining stress have been colle...Based on the engineering project on a small coal pillar of 12,521 working face roadway in Xieqiao Coalmine, data regarding surface displacements of the coal pillar, deep displacements and mining stress have been collected and analyzed. The results show that macroscopic transverse fractures of the inner coal pillar are developed within 2–4 m of the roadway surface, which is located outside the coal pillar anchorage zone. There is a displacement of 530 mm at the monitoring point in the 6 m deep zone of the pillar. Transfer of the fracture zone is found in a small coal pillar and the fractures within 3–4 m of the coal-rock zone from the roadway surface undergo propagation and closure of cracks which means this fracture zone is transferred from 3–4 m outside the roadway to only 2–3 m from the roadway surface. In the monitoring zone, vertical and horizontal stresses increase with a feature that shows that acceleration in the deep zone of the pillar is greater than that in the shallow zone. Furthermore, the acceleration of vertical stress is also greater than that of horizontal stress with a peak value in the 4 m zone.The research findings provide a reference for the regulation of a reasonable width of coal pillar in coalmines and optimal control design of surrounding rock.展开更多
In order to obtain the distribution rules of abutment pressure around the 1151 （3） fully mechanized top-coal caving （FMTC） face of Xieqiao Colliery, the KSE-II-1 type bore-hole stress gauges were installed in the ...In order to obtain the distribution rules of abutment pressure around the 1151 （3） fully mechanized top-coal caving （FMTC） face of Xieqiao Colliery, the KSE-II-1 type bore-hole stress gauges were installed in the tailentry and headentry to measure the mining-induced stress. The distribution rules of the front and side abutment pressure were demonstrated. The results show that distribution rules of stress are obviously different in the vicinity of the face and entries. The peak value of abutment pressure in the protective coal pillar and face are located commonly in front of the working face along the strike, and they are located at the stress-decreased zone near the face. There is no stress peak value in the lateral coal mass beside the headentry in front of the face on the strike, and the peak value of abutment pressure appears at the rear area of the face. There are stress peak values both in the protective coal pillar and in the lateral coal mass beside the headentry to the dip.展开更多
The three-dimensional damage constitutive relationship of coal is established and distribution law of the abutment pressure of the integrated coal beside the road-in packing for gob-side entry retaining in fully-mecha...The three-dimensional damage constitutive relationship of coal is established and distribution law of the abutment pressure of the integrated coal beside the road-in packing for gob-side entry retaining in fully-mechanized caving face under the effect of given deformation of the main roof is analyzed by the damage mechanics theory. And the relationship between distribution of the abutment pressure and thickness of coal seam is explored. The presented result is of great theoretical significance and practical value to the study on stability control of the surrounding rock of road-in packing for gob-side entry retaining in fully-mechanized caving face.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 40874070,40904028 and 51104156)the Self-Researched Subject of State Key Laboratory of Coal Resources and Mine Safety (No. SKLCRSM09X01)the Specialized Fund for the Basic Research Operating Expenses Program of Central College (No. 2010QNB01)
文摘The front abutment pressure of a fully-mechanized workface of 11061 soft coal isolated island of Liangbei Coal Mine was measured and studied using a self-developed mining-induced stress monitoring system associated with electromagnetic radiation technology, and the effects of abutment pressure distribution on strata behavior we discussed. The results indicate that the miningdnduced influencing distance advanced at the fully-mechanized working face of soft coal isolated island is larger than that at the gen- eral working face at the isolated island, besides the fracture zone in front of working face was widened to some extent, and the influencing range caused by relaxations on both roadways became bigger with the advancing working face. Moreover, it can be indicated that mining has significant effect on strata behav- ior of fully-mechanized working face of soft coal isolated island, which is mostly distributed in the area of stress concentration. The research results have an important reference value for revealing the distribution pattern of the front abutment pressure of a fully-mechanized working face of soft coal isolated island, and controlling the coal-rock dynamic disaster occurrence under similar mining conditions.
基金the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT1084)the Open Fund of Hunan provincial Key Laboratory for Safe Mining Technology of Coal Mine (No. 201103)the National Natural Science Foundation of China (No. 51274193)
文摘Based on the engineering project on a small coal pillar of 12,521 working face roadway in Xieqiao Coalmine, data regarding surface displacements of the coal pillar, deep displacements and mining stress have been collected and analyzed. The results show that macroscopic transverse fractures of the inner coal pillar are developed within 2–4 m of the roadway surface, which is located outside the coal pillar anchorage zone. There is a displacement of 530 mm at the monitoring point in the 6 m deep zone of the pillar. Transfer of the fracture zone is found in a small coal pillar and the fractures within 3–4 m of the coal-rock zone from the roadway surface undergo propagation and closure of cracks which means this fracture zone is transferred from 3–4 m outside the roadway to only 2–3 m from the roadway surface. In the monitoring zone, vertical and horizontal stresses increase with a feature that shows that acceleration in the deep zone of the pillar is greater than that in the shallow zone. Furthermore, the acceleration of vertical stress is also greater than that of horizontal stress with a peak value in the 4 m zone.The research findings provide a reference for the regulation of a reasonable width of coal pillar in coalmines and optimal control design of surrounding rock.
基金Supported by the National Natural Science Foundation of Anhui Province （K J2010A090）
文摘In order to obtain the distribution rules of abutment pressure around the 1151 （3） fully mechanized top-coal caving （FMTC） face of Xieqiao Colliery, the KSE-II-1 type bore-hole stress gauges were installed in the tailentry and headentry to measure the mining-induced stress. The distribution rules of the front and side abutment pressure were demonstrated. The results show that distribution rules of stress are obviously different in the vicinity of the face and entries. The peak value of abutment pressure in the protective coal pillar and face are located commonly in front of the working face along the strike, and they are located at the stress-decreased zone near the face. There is no stress peak value in the lateral coal mass beside the headentry in front of the face on the strike, and the peak value of abutment pressure appears at the rear area of the face. There are stress peak values both in the protective coal pillar and in the lateral coal mass beside the headentry to the dip.
基金Supported by the National Science Foundation of China (50874042, 50674046)National Science Important Foundation (50634050)Hunan Science Foundation (06JJ50092)
文摘The three-dimensional damage constitutive relationship of coal is established and distribution law of the abutment pressure of the integrated coal beside the road-in packing for gob-side entry retaining in fully-mechanized caving face under the effect of given deformation of the main roof is analyzed by the damage mechanics theory. And the relationship between distribution of the abutment pressure and thickness of coal seam is explored. The presented result is of great theoretical significance and practical value to the study on stability control of the surrounding rock of road-in packing for gob-side entry retaining in fully-mechanized caving face.
