东同V号矿体充填体下阶段矿柱稳定性分析

发布时间：2018-04-09 18:40

本文选题：充填体下　切入点：阶段矿柱　出处：《江西理工大学》2015年硕士论文

【摘要】：随着人类社会的发展,埋藏较浅的矿产资源储量日益减少,所以向地下深部开采资源和在各种复杂条件下回采矿体成为大势所趋。为更多的回收资源和保护地表,对上部采空区进行充填成为必要的手段,导致开采深部矿体的技术条件更为复杂。充填体下采矿有其特殊性:尾砂、废石等充填料散体对其下部结构产生垂直荷载,改变了结构的受力状态;输送充填体的水弱化岩体,使岩体强度降低;由于充填体微观上不可避免的含有微裂隙、微缺陷特性,爆破震动的累积作用很明显,对充填体稳定性造成不利影响。本文结合东乡铜矿V号矿体的复杂条件和开采现状,进行了充填体下阶段矿柱稳定性研究。论文主要所做工作及结论如下:(1)采用AHP分析方法得出了影响充填体下阶段矿柱稳定性的几个较重要的因素。单元结构参数在目标层中权重较高,即结构参数对充填体下阶段矿柱稳定性影响较大,故在开采设计时需加以重视。采场暴露面积、阶段矿柱厚度在准则层的结构参数中权重较高;岩体结构、开采深度在准则层的地质条件中权重较高;爆破震动、上部充填高度在准则层的工程条件中权重较高。研究结果认为,岩体结构、开采深度受自然条件决定,采场暴露面积、阶段矿柱厚度、爆破震动是可控参数,采矿时,应予以重视。(2)介绍了小变形薄板理论的公式,并计算确定阶段矿柱最小安全厚度为5m,建立了数值模型进一步模拟,对阶段矿柱厚度从5m至9m进行了分析,得出了在采场宽度为15m,回采单元长为25m,暴露面积为375m2时,阶段矿柱厚度为7m符合要求。(3)利用ANSYS软件的LS-DYNA模块,模拟了上部为充填体、下部为分段采场、药包分段延时爆破的过程。结果表明:矿柱应力分布随着不同药包起爆的能量发生叠加,导致矿柱最大应力相应增大,但仍然小于矿岩的抗拉强度,比抗压、抗剪强度更小,所以不会对矿岩的稳定性造成不利影响;炸药爆破作用,对矿柱产生位移,Z方向最大位移随爆破次数的叠加而增大;爆破震动经过阶段矿柱的隔离作用,对充填体产生的最大有效应力小于充填体的抗压强度,上部充填体的稳定性不会被破坏。
[Abstract]:With the development of human society, the reserves of shallow mineral resources are decreasing day by day.In order to recover more resources and protect the surface, filling the upper goaf becomes a necessary means, which makes the technical conditions of mining deep orebody more complicated.Mining under the filling body has its particularity: vertical load on the substructure of the filling material such as tailings, waste rock and so on, which changes the stress state of the structure, the water weakening of the conveying filling body makes the rock mass strength decrease;Because of the microfissures and microdefects in the backfill, the accumulative effect of blasting vibration is obvious, which has an adverse effect on the stability of the backfill.Based on the complex conditions and mining status of No. V orebody in Dongxiang Copper Mine, the stability of pillar in the lower stage of filling body is studied in this paper.The main work and conclusions of this paper are as follows: (1) by using AHP analysis, several important factors affecting the stability of pillar in the lower stage of the filling body are obtained.The structural parameters of the unit have a high weight in the target layer, that is, the structural parameters have a great influence on the stability of the pillar under the filling body, so it is necessary to pay attention to the mining design.The upper filling height has a high weight in the engineering condition of the criterion layer.Therefore, the stability of ore rock will not be adversely affected; the blasting action of explosive, the maximum displacement of Z direction to the pillar will increase with the superposition of blasting times; the isolating action of pillar in the stage of blasting vibration,The maximum effective stress on the filling is less than the compressive strength of the filling, and the stability of the upper filling will not be destroyed.
【学位授予单位】：江西理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD853.34

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