存在采空区的台阶爆破效果评价及参数优化

发布时间：2019-03-24 10:49

【摘要】：山西平朔东露天煤矿,鉴于地表下存在采空区,台阶爆破技术需要进一步优化,以降低大块率、后裂、炮孔冲孔、炸药单耗,改善爆破振动对采空区顶板和土质边坡稳定性影响。针对台阶爆破现阶段的问题,采用模糊数学层次分析法,建立爆破效果评价模型,对爆破效果进行评价;采用ANSYS模拟爆破振动对采空区顶板稳定性的影响;在保证采空区安全稳定的基础上,通过LS-DYNA模拟和现场试验对比的方法,对台阶爆破参数进行优化。针对东露天存在采空区的实际情况,通过研究,主要有以下研究成果:(1)依据东露天矿存在地下采空区的实际情况,选取3个一级评价指标和10个二级评价指标,建立各级指标的层次结构图,依据层次结构图确定各级指标的权重和隶属函数,最后建立东露天矿台阶爆破效果评价模型,对优化前台阶爆破效果做出综合的分析评价。得出东露天矿台阶爆破仍存在一些问题,需要进一步优化;台阶爆破与采空区的安全距离为200米;顶板最小安全厚度为35米。(2)在评价的基础上,依据东露天现有设备和爆破设计软件,设计爆破参数的优化方案,采用LS-DYNA对爆破参数模拟,分析对比不同爆破参数下爆破效果的模拟结果。得到采用孔网参数7×6,矩形布孔方式的一组参数爆破效果最佳。(3)根据LS-DYNA的模拟结果,得出一套最佳的布孔方式和孔网参数,再通过现场对比试验加以验证。与现场试验的爆破效果比较后,爆破效果比较吻合,验证优化后的爆破参数是合理的。以上研究成果表明,存在采空区的东露天矿台阶爆破技术有待进一步改进,优化后的爆破参数确实改善了爆破效果,同时采空区顶板稳定性也得到了解决,达到了预期的目标。
[Abstract]:In the east opencast coal mine of Pingshuo, Shanxi Province, in view of the existence of goaf under the surface, the bench blasting technology needs to be further optimized in order to reduce the bulk ratio, the back crack, the hole piercing, and the explosive unit consumption. The influence of blasting vibration on the stability of roof and soil slope in goaf is improved. Aiming at the problems of bench blasting at present stage, the fuzzy mathematics analytic hierarchy process (AHP) is used to establish the blasting effect evaluation model and the blasting effect is evaluated, and the influence of blasting vibration on the roof stability of goaf is simulated by ANSYS. On the basis of ensuring the safety and stability of goaf, the parameters of bench blasting are optimized by means of LS-DYNA simulation and field test. According to the actual situation of the goaf in the east opencast, the main research results are as follows: (1) according to the actual situation of the underground goaf in the east open pit mine, three first-class evaluation indexes and ten second-level evaluation indexes are selected. The hierarchical structure diagram of each level index is established, the weight and membership function of each index are determined according to the hierarchical structure diagram. Finally, the evaluation model of bench blasting effect of east open-pit mine is established, and the comprehensive analysis and evaluation are made to optimize the blasting effect of front step. It is concluded that there are still some problems in bench blasting in East Open-pit Mine, which need further optimization, and the safety distance between bench blasting and goaf is 200 meters. The minimum safety thickness of roof is 35 meters. (2) on the basis of evaluation, according to the existing equipment and blasting design software, the optimization scheme of blasting parameters is designed, and the blasting parameters are simulated by LS-DYNA. The simulation results of blasting effect under different blasting parameters are analyzed and compared. The blasting effect of a group of parameters with hole mesh parameter 7 脳 6 and rectangular hole arrangement is obtained. (3) according to the simulation results of LS-DYNA, a set of optimum hole arrangement mode and hole network parameters are obtained, and then verified by field comparison test. Compared with the blasting effect of the field test, the blasting effect is more consistent, and the optimized blasting parameters are proved to be reasonable. The above research results show that the bench blasting technology of the East Open-pit Mine existing in goaf needs to be further improved, and the optimized blasting parameters do improve the blasting effect, and the roof stability of goaf is also solved and the expected goal is achieved.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD235

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