论文标题:孤岛工作面覆岩运动破坏规律研究
Study on the Law of the Movement and Fracture of "Isolated Island" Working Face Ovenburden
论文作者 张恒
论文导师 吴士良,论文学位 硕士,论文专业 采矿工程
论文单位 山东科技大学,点击次数 166,论文页数 95页File Size4548k
2004-06-01论文网 http://www.lw23.com/lunwen_97893872/ 孤岛开采;覆岩破坏;临界尺寸;支承压力
isolated island face extracted;overburden fracture;the critical area abutment pressure
论文围绕孤岛工作面开采前后，覆岩断裂破坏特征及孤岛煤体支承压力分布规律等问题开展研究工作。根据组合梁理论确定了岩层载荷及岩层发生断裂破坏的条件，由此得到了采场充分采动临界开采范围的定义和计算公式，并得出了充分采动和非充分采动条件下，覆岩断裂破坏最大高度和两种的破坏区域形态，分别为“凹”形和“凸”形。讨论了两侧采动范围不同时，孤岛覆岩断裂破坏特征：(1)覆岩破坏区域连成一个整体；(2)覆岩断裂破坏最大高度与两侧采空范围相关，两侧大于临界采空范围时，孤岛覆岩断裂破坏最大高度不会增大；只有一侧大于临界范围，该侧覆岩断裂破坏最大高度不会增大，而小于临界开采尺寸侧覆岩破坏高度增加；两侧都小于临界采空范围，孤岛覆岩断裂破坏最大高度与整体采空范围有关，该值大于临界范围，覆岩断裂破坏最大高度和破坏区域形态与充分采动相似，该值小于临界采空范围，覆岩断裂破坏高度和破坏区域形态与非充分采动相似。 根据覆岩断裂和传递力的特征，研究得到孤岛煤体支承压力与两侧采空尺寸有关，两侧采空尺寸向临界开采范围增大过程中，支承压力平均集中系数逐渐增大；两侧大于临界开采尺寸后，平均支承压力集中系数保持不变，并给出了计算公式。根据煤体支承压力分布特征得到最小孤岛煤体可开采尺寸与两侧采空范围相关的结论，并给出了计算公式。结合兖矿集团济宁二号煤矿23_下03孤岛工作面实际条件进行的数值模拟和现场实测研究，较好地验证了上述研究结论。
The thesis studies the character of overburden ,the law of distribution of abutment pressure ,etc ,before isolated island face mined and after. According to the compound beam theory confirm the load on the rock stratum, analyze the condition destroyed that the rock stratum breaks. And make out the critical area of supercritical mining and get the corresponding calculation formula. And under the supercritical or non-supercritical mining ,gain two different kinds of the largest fracture height of overburden and fracture region shape. Under the different mining area of both sides, talk about the character of overburden fracture of isolated island face, (l)the overburden fracture region links a whole, (2)the largest fracture height related to the gob area of both sides, when the both sides are larger than the critical area, the overburden fracture height of the isolated island face does not increase, when only one gob area of the both is larger than the critical area, the overburden fracture height of isolated island face mined does not increase too, but lead to increase in the other and when the gob areas of both sides is smaller than the critical area, the overburden fracture height of isolated island face mined will increase and it is relate to the whole gob area, if the whole gob area is larger than the critical area, the largest overburden fracture height and the fracture region shape is similar to that of the supercritical mining, if the whole gob area is smaller than the critical, the fracture region shape is similar to that of the non-supercritical mining.According to the character of fracture and deliver power, study relation of abutment pressure of isolated island face and the gob area of both sides. And receive the conclusion that gob area of the both sides and abutment pressure of isolated island is relate. When the gob area reaching to the critical area, the concentrated coefficient of abutment pressure increase too,. And when it is larger than the critical area, the coefficient keeps intact. Provide the calculation formula of the coefficient. According to the character of abutment pressure, receive the conclusion that the minimum size to extract is relate to the gob area of the both sides, and provide the formula. Combine the 2303 isolated island face of lining No.2 colliery, and carry on studying by numerical simulation and project example ,that prove above mentioned conclusion.
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