On-site investigations consistently show that the rock burst inherent to coal seams varies greatly with coal seam thickness.In this study,impact factors related to coal seam thickness and surrounding rock strength wer...On-site investigations consistently show that the rock burst inherent to coal seams varies greatly with coal seam thickness.In this study,impact factors related to coal seam thickness and surrounding rock strength were analyzed and a corresponding rock burst risk assessment method was constructed.The model reflects the influence of coal seam thickness on the stress distribution of surrounding rock at the roadway.Based on the roadway excavation range,a stress distribution model of surrounding roadway rock is established and the influence of coal seam thickness on rock burst risk is analyzed accordingly.The proposed rock burst risk assessment method is based on the equivalent surrounding rock strength and coal seam bursting liability.The proposed method was tested in a 3500 mining area to find that it yields rock burst risk assessment results as per coal seam thickness that are in accordance with real-world conditions.The results presented here suggest that coal seam thickness is a crucial factor in effective rock burst risk assessment.展开更多
Rock burst is one of the most catastrophic dynamic hazards in coal mining. A static and dynamic stresses superposition-based(SDSS-based) risk evaluation method of rock burst was proposed to pre-evaluate rock burst ris...Rock burst is one of the most catastrophic dynamic hazards in coal mining. A static and dynamic stresses superposition-based(SDSS-based) risk evaluation method of rock burst was proposed to pre-evaluate rock burst risk. Theoretical basis of this method is the stress criterion incurring rock burst and rock burst risk is evaluated according to the closeness degree of the total stress(due to the superposition of static stress in the coal and dynamic stress induced by tremors) with the critical stress. In addition, risk evaluation criterion of rock burst was established by defining the "Satisfaction Degree" of static stress. Furthermore,the method was used to pre-evaluate rock burst risk degree and prejudge endangered area of an insular longwall face in Nanshan Coal Mine in China. Results show that rock burst risk is moderate at advance extent of 97 m, strong at advance extent of 97-131 m,and extremely strong(i.e. inevitable to occur) when advance extent exceeds 131 m(mining is prohibited in this case). The section of two gateways whose floor abuts 15-3 coal seam is a susceptible area prone to rock burst. Evaluation results were further compared with rock bursts and tremors detected by microseismic monitoring. Comparison results indicate that evaluation results are consistent with microseismic monitoring, which proves the method's feasibility.展开更多
This study presents a novel approach using theoretical analysis to assess the risk of rock burst of an island longwall panel that accounts for the coupled behavior of stress distribution and overlying strata movement....This study presents a novel approach using theoretical analysis to assess the risk of rock burst of an island longwall panel that accounts for the coupled behavior of stress distribution and overlying strata movement. The height of destressed zone(HDZ) above the mined panel was first determined based on the strain energy balance in an underground coal mining area. HDZ plays a vital role in accurately determining the amount of different loads being transferred towards the front abutment and panel sides. Subsequently, based on the load transfer mechanisms, a series of formulae were derived for the average static and dynamic stresses in the island pillar through theoretical analysis. Finally, the model was applied to determining the side abutment stress distribution of LW 3112 in the Chaoyang Coal Mine and the results of ground subsidence monitoring were used to verify the predicted model. It can be concluded that the proposed computational model can be successfully applied to determining the safety of mining in island longwall panels.展开更多
冲击地压作为煤矿生产过程中常见的动力灾害,给煤矿安全生产带来极大威胁,因此,工作面回采前进行冲击危险性评价尤为重要。为构建冲击地压危险性的科学评价模型,本文收集和研究了140个煤矿工作面实例,分析了冲击地压的影响因素,从每个...冲击地压作为煤矿生产过程中常见的动力灾害,给煤矿安全生产带来极大威胁,因此,工作面回采前进行冲击危险性评价尤为重要。为构建冲击地压危险性的科学评价模型,本文收集和研究了140个煤矿工作面实例,分析了冲击地压的影响因素,从每个案例中提取14项评价指标,并建立了数据库。基于数量化理论评价法与模糊评价法,建立了适用性更强的TWF(theory of quantification with fuzzy evaluation)评价法,该方法继承了数量化理论和模糊评价法的优势,并将煤矿冲击危险程度划分为5个等级。以河南某煤矿工作面为背景,采用TWF冲击危险性评价模型对该工作面进行了冲击危险性评价,得出危险性指数为19.83,评价结果为无冲击危险性,与现场实际相符,表明该评价模型具有较强的适用性;开发了TWF综合评价系统,持续的案例补充可不断提高TWF评价模型的评价精度,研究成果可为冲击地压危险评价提供一定的理论参考。展开更多
基金supported and financed from Special Funds for Basic Research Business Fees of China Academy of Safety Science and Technology(Nos.2016JBKY16,2017JBKY05)National Key Research and Development Program of China(No.2017YFC0804603)Subject of Beijing Science and Technology Commission(No.Z171100002317008)
文摘On-site investigations consistently show that the rock burst inherent to coal seams varies greatly with coal seam thickness.In this study,impact factors related to coal seam thickness and surrounding rock strength were analyzed and a corresponding rock burst risk assessment method was constructed.The model reflects the influence of coal seam thickness on the stress distribution of surrounding rock at the roadway.Based on the roadway excavation range,a stress distribution model of surrounding roadway rock is established and the influence of coal seam thickness on rock burst risk is analyzed accordingly.The proposed rock burst risk assessment method is based on the equivalent surrounding rock strength and coal seam bursting liability.The proposed method was tested in a 3500 mining area to find that it yields rock burst risk assessment results as per coal seam thickness that are in accordance with real-world conditions.The results presented here suggest that coal seam thickness is a crucial factor in effective rock burst risk assessment.
基金Project(51174285)supported by the National Natural Science Foundation of China and the Shenhua Group Corporation Limited,ChinaProject(CXZZ12_0949)supported by the Research and Innovation Project for College Graduates of Jiangsu Province,ChinaProject(SZBF2011-6-B35)supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China
文摘Rock burst is one of the most catastrophic dynamic hazards in coal mining. A static and dynamic stresses superposition-based(SDSS-based) risk evaluation method of rock burst was proposed to pre-evaluate rock burst risk. Theoretical basis of this method is the stress criterion incurring rock burst and rock burst risk is evaluated according to the closeness degree of the total stress(due to the superposition of static stress in the coal and dynamic stress induced by tremors) with the critical stress. In addition, risk evaluation criterion of rock burst was established by defining the "Satisfaction Degree" of static stress. Furthermore,the method was used to pre-evaluate rock burst risk degree and prejudge endangered area of an insular longwall face in Nanshan Coal Mine in China. Results show that rock burst risk is moderate at advance extent of 97 m, strong at advance extent of 97-131 m,and extremely strong(i.e. inevitable to occur) when advance extent exceeds 131 m(mining is prohibited in this case). The section of two gateways whose floor abuts 15-3 coal seam is a susceptible area prone to rock burst. Evaluation results were further compared with rock bursts and tremors detected by microseismic monitoring. Comparison results indicate that evaluation results are consistent with microseismic monitoring, which proves the method's feasibility.
基金Project(2017CXNL01) supported by the Fundamental Research Funds for the Central Universities,China
文摘This study presents a novel approach using theoretical analysis to assess the risk of rock burst of an island longwall panel that accounts for the coupled behavior of stress distribution and overlying strata movement. The height of destressed zone(HDZ) above the mined panel was first determined based on the strain energy balance in an underground coal mining area. HDZ plays a vital role in accurately determining the amount of different loads being transferred towards the front abutment and panel sides. Subsequently, based on the load transfer mechanisms, a series of formulae were derived for the average static and dynamic stresses in the island pillar through theoretical analysis. Finally, the model was applied to determining the side abutment stress distribution of LW 3112 in the Chaoyang Coal Mine and the results of ground subsidence monitoring were used to verify the predicted model. It can be concluded that the proposed computational model can be successfully applied to determining the safety of mining in island longwall panels.
文摘冲击地压作为煤矿生产过程中常见的动力灾害,给煤矿安全生产带来极大威胁,因此,工作面回采前进行冲击危险性评价尤为重要。为构建冲击地压危险性的科学评价模型,本文收集和研究了140个煤矿工作面实例,分析了冲击地压的影响因素,从每个案例中提取14项评价指标,并建立了数据库。基于数量化理论评价法与模糊评价法,建立了适用性更强的TWF(theory of quantification with fuzzy evaluation)评价法,该方法继承了数量化理论和模糊评价法的优势,并将煤矿冲击危险程度划分为5个等级。以河南某煤矿工作面为背景,采用TWF冲击危险性评价模型对该工作面进行了冲击危险性评价,得出危险性指数为19.83,评价结果为无冲击危险性,与现场实际相符,表明该评价模型具有较强的适用性;开发了TWF综合评价系统,持续的案例补充可不断提高TWF评价模型的评价精度,研究成果可为冲击地压危险评价提供一定的理论参考。
