Simulated comminution that the coal impact rigid wall using finite element soft- ware of explicit formulation based on dynamics model of elastic collision (Hamilton varia- tionnal principle),the critical velocity of t...Simulated comminution that the coal impact rigid wall using finite element soft- ware of explicit formulation based on dynamics model of elastic collision (Hamilton varia- tionnal principle),the critical velocity of the coal impacting comminution was about 10 m/s, and validated the release effect of pressure in the coal impacting comminution,and then extend applied field of the finite element software of explicit formulation LS-DYNA analys- ing impact comminution of the elastic-plastic material.The simulation result has great guidance and reference value for understanding the impact comminution mechanics of coal and other material and manufacturing comminution equipment.展开更多
Based on the geological condition of Zhangxiaolou deep mine in Xuzhou mining area, under 986 m in depth, 20.6-31.6 MPa in maximum horizontal principal stress, and friable and fractured surrounding rock, test researche...Based on the geological condition of Zhangxiaolou deep mine in Xuzhou mining area, under 986 m in depth, 20.6-31.6 MPa in maximum horizontal principal stress, and friable and fractured surrounding rock, test researches on partial relieving pressure were completed for the entry with U-steel arched yielding support. The relieving pressure parameters, technology process and results of springing blasting by boreholes and excavating pockets in the two sides of entry were introduced. It is demonstrated that springing will not be shaped under the condition of single borehole arrangement after exploded, the arrangement by a group, it will make borehole bottom form springing in 0.6-0.8 m in diameter, that convergence of two sides and roof to floor have some increments by using springing blasting for reliving pressure. This kind of method for reliving pressure is not suitable to use in the deep mine, and that the convergence of two sides obviously declined by excavating pocket in two sides, it can be still used in the entry with metal support, while maintenance of entry in deep mines is difficult, and can not be supported by bolt or bolt with wire mesh.展开更多
Rock bursts are spontaneous, violent fracture of rock that can occur in deep mines, and the likelihood of rock bursts occurring increases as depth of the mine increases. Rock bursts are also affected by the compressiv...Rock bursts are spontaneous, violent fracture of rock that can occur in deep mines, and the likelihood of rock bursts occurring increases as depth of the mine increases. Rock bursts are also affected by the compressive strength, tensile strength, tangential strength, elastic energy index, etc. of rock, and the relationship between these factors and rock bursts in deep mines is difficult to analyze from quantitative point. Typical rock burst instances as a sample set were collected, and membership function was introduced to process the discrete values of these factors with the discrete factors as condition attributes and rock burst situations as decision attributes. Dominance-based rough set theory was used to generate preference rules of rock burst, and eventually rock burst laws analysis in deep mines with preference relation was taken. The results show that this model for rock burst laws analysis in deep mines is more reasonable and feasible, and the prediction results are more scientific.展开更多
By using the continuous exploration system with multi-pipeline in the borehole, the failure cracks of cover strata (specially, the small cracks developing) after the combined mining of 16, 17 thin seams of the 4th min...By using the continuous exploration system with multi-pipeline in the borehole, the failure cracks of cover strata (specially, the small cracks developing) after the combined mining of 16, 17 thin seams of the 4th mining block in Zhaopo Mine is explored. After that, the researching result is considered as the output and the testing result of rock mechanics parameters is considered as the verifying data, the back analysis is made with the conception of the point safety degree. The relative height of the crack developing is obtaied. So, the evaluating of the safety of 16, 17 seams combined mining under the gob water with extreme distance is made and the mining has been safety. The scientific basis is provided for the evaluating of the mining safety with the similar conditions.展开更多
文摘Simulated comminution that the coal impact rigid wall using finite element soft- ware of explicit formulation based on dynamics model of elastic collision (Hamilton varia- tionnal principle),the critical velocity of the coal impacting comminution was about 10 m/s, and validated the release effect of pressure in the coal impacting comminution,and then extend applied field of the finite element software of explicit formulation LS-DYNA analys- ing impact comminution of the elastic-plastic material.The simulation result has great guidance and reference value for understanding the impact comminution mechanics of coal and other material and manufacturing comminution equipment.
基金Supported by the Key Project of the National Natural Science Foundation （50490273）
文摘Based on the geological condition of Zhangxiaolou deep mine in Xuzhou mining area, under 986 m in depth, 20.6-31.6 MPa in maximum horizontal principal stress, and friable and fractured surrounding rock, test researches on partial relieving pressure were completed for the entry with U-steel arched yielding support. The relieving pressure parameters, technology process and results of springing blasting by boreholes and excavating pockets in the two sides of entry were introduced. It is demonstrated that springing will not be shaped under the condition of single borehole arrangement after exploded, the arrangement by a group, it will make borehole bottom form springing in 0.6-0.8 m in diameter, that convergence of two sides and roof to floor have some increments by using springing blasting for reliving pressure. This kind of method for reliving pressure is not suitable to use in the deep mine, and that the convergence of two sides obviously declined by excavating pocket in two sides, it can be still used in the entry with metal support, while maintenance of entry in deep mines is difficult, and can not be supported by bolt or bolt with wire mesh.
基金Project(2011AA060407) supported by the National High Technology Research and Development Program of China
文摘Rock bursts are spontaneous, violent fracture of rock that can occur in deep mines, and the likelihood of rock bursts occurring increases as depth of the mine increases. Rock bursts are also affected by the compressive strength, tensile strength, tangential strength, elastic energy index, etc. of rock, and the relationship between these factors and rock bursts in deep mines is difficult to analyze from quantitative point. Typical rock burst instances as a sample set were collected, and membership function was introduced to process the discrete values of these factors with the discrete factors as condition attributes and rock burst situations as decision attributes. Dominance-based rough set theory was used to generate preference rules of rock burst, and eventually rock burst laws analysis in deep mines with preference relation was taken. The results show that this model for rock burst laws analysis in deep mines is more reasonable and feasible, and the prediction results are more scientific.
文摘By using the continuous exploration system with multi-pipeline in the borehole, the failure cracks of cover strata (specially, the small cracks developing) after the combined mining of 16, 17 thin seams of the 4th mining block in Zhaopo Mine is explored. After that, the researching result is considered as the output and the testing result of rock mechanics parameters is considered as the verifying data, the back analysis is made with the conception of the point safety degree. The relative height of the crack developing is obtaied. So, the evaluating of the safety of 16, 17 seams combined mining under the gob water with extreme distance is made and the mining has been safety. The scientific basis is provided for the evaluating of the mining safety with the similar conditions.
