合理的采场结构参数可使采场处于有利的力学状态,使围岩的应力、应变分布趋于均匀化,在保证开采系统稳定和生产安全的前提下,减少支护工作量,提高采矿强度和生产效率。在深入分析思山岭铁矿地质概况与采矿方法的基础上,对影响矿房回采稳定性的矿房高度、矿房宽度、采场长度、矿柱宽度、矿柱充填方式等5个关键因素进行2水平正交设计,获得8种试验方案。运用大型岩土软件FLAC^3D对盘区内不同方案的采场结构参数进行数值模拟研究,分析其在不同结构参数下应力、位移、塑性区等特征,初步得出采场处于最有利力学状态时的结构参数方案(采场高60m、采场长60m,矿房宽18m、矿柱宽20m的参数方案)。计算结果表明:回采过程中,采场长度对顶板应力和顶板位移的影响最大,采场越长,应力值越大,且压应力主要在盘区间柱集中,顶底板处出现拉应力集中。分析结果可为盘区矿房矿柱的安全高效回采提供技术支持。
Rational stope structural parameters may lead to a favorable mechanic state for the stopes and the stress and strain distribution of the wall rocks may become more homogenized. Under this condition, support workload is reduced and the mining intensity as well as the production efficiency can be improved on the premise of ensuring the stable exploring system and safe production. Based on the geological situation and mining methods of Sishanling iron ore, two-level orthogonal experi- mental design is made to decide the key five factors affecting the room exploring stability, i. e. room height, room width, stope length, pillar width and pillar filling method. Then, eight experimental schemes are concluded. The finite-difference software FLAC3D is adopted to make numerical simulation on the stope structural parameters of different scheme at panel, and to obtain the feature of the stress, displacement, and plastic zone under different structural parameters. It is preliminarily obtained that the optimal structure parameters which can stabilize the stope is the height of stope 60 m, the length of stope 60 m, the width of room 18m ,and the width of pillar 20 m. The calculating results show that the stope length of the roof influences the stress and roof displacement maximum, i. e. the longer the stope, the greater the stress. The compressive stress mainly concentrates on the panel pillars, while the tensile stress concentrates on the roof and the bottom. The results may provide technical support for safe and efficient mining of rooms and pillars within panel.