综放开采顶煤与覆岩力链结构及演化光弹试验研究

发布时间：2018-05-29 09:33

本文选题：煤矿开采 + 煤　；参考：《工程科学学报》2017年01期

【摘要】：综放开采过程中顶煤和覆岩由连续向非连续和散体介质状态转变,描述矿压在断裂覆岩和碎裂顶煤中的形成、传递方式和作用机理是综放开采矿压理论研究的难点.基于光弹试验原理,借助散体介质双轴加载双向流动光弹试验装置,对综放开采过程中散体顶煤与非连续覆岩关键层中力链网络结构及演化特征进行研究.研究发现:地层载荷在煤岩体中构成了错综复杂的弱-强力链网络.综放开采打破了初始力链网络结构的平衡,顶煤与覆岩中形成梁-拱复合力链拱结构,覆岩荷载以强力链形式传递到工作面前方煤体.随着工作面推进和顶煤放出,覆岩梁-拱力链网络不断扩展和演化,形成更大规模的力链拱结构.关键层弯曲、断裂和失稳运动,使工作面前方的强力链拱脚出现回缩现象,力链分布密度和强度增加,导致工作面来压现象.地层内水平力作用使顶煤与覆岩内的梁-拱力链结构效应较更加明显,整体拱结构形态愈加完整,强力链网络结构更加紧致,关键层断裂失稳时力链拱对工作面煤层的作用力更加显著.
[Abstract]:In the process of fully mechanized caving mining, the state of top coal and overburden rock changed from continuous to discontinuous and scattered medium, and the formation of rock pressure in fracture overburden and broken top coal was described. The transmission mode and action mechanism are the difficult points in the theoretical study of fully mechanized caving mining pressure. Based on the principle of photoelastic test and with the aid of biaxial loading biaxial flow photoelastic test device of bulk medium, the network structure and evolution characteristics of force chain in the critical strata of loose top coal and discontinuous overburden during fully mechanized caving mining are studied. It is found that the formation load constitutes a complex weak-strength chain network in coal and rock mass. Full-mechanized caving mining broke the balance of initial force chain network structure and formed a beam-arch composite force chain arch structure between top coal and overburden rock. The overburden load was transferred to the coal body in front of the face in the form of strong chain. With the working face advancing and the top coal drawing, the overburden beam-arch force chain network expands and evolves continuously, forming a larger force chain arch structure. The bending, fracture and unstable movement of the key layer make the arch foot of the strong chain in front of the face shrink back, and the distribution density and strength of the force chain increase, which leads to the pressure phenomenon in the working face. The horizontal force in the stratum makes the beam-arch chain structure effect more obvious in top coal and overburden rock, the integral arch structure is more complete, and the network structure of strong chain is more compact. The force chain arch acting on the coal seam is more obvious when the key layer fracture is unstable.
【作者单位】：北京科技大学土木与资源工程学院;金属矿山高效开采与安全教育部重点实验室;中国白城兵器试验中心;
【分类号】：TD323

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