基于FLAC~(2D)的空场嗣后充填法采场结构参数优化

为了探明缓倾斜中厚矿体空场嗣后充填法在不同采场结构参数及不同回采阶段的采场稳定性,引进FLAC2D软件对采场宽度分别为32m、36m及40m时在三种回采阶段的应力、位移和塑性区分布规律进行二维数值模拟。结果表明,充填体理想弹塑性本构模型及矿岩应变软化本构模型适用于矽卡岩矿体,不同开采扰动及矿房跨度条件下采场稳定性不同,当采场沿走向宽度36m以下时最大主应力、最小主应力、塑性区分布及顶板竖直位移在安全范围之内。优化后的采场结构参数为采场沿走向宽度36m,其中矿房31m、间柱5m,实践证明该方案在安全性及经济性上能满足生产要求。

Stope Structural Parameters Optimization for Open Stoping with Subsequent Backfilling on the Basis of FLAC2D

To investigate stope stabilities under conditions of different structural parameters and mining steps in open stope mining with sequent backfilling for flat - lying medium - thick deposit, FLAC2D software was introduced to simulate the stress, settlement and plastic zone distribution. The two - dimensional simulations involved three mining steps where stope width was set as 32m, 36m and gOm, respectively. Results showed that the ideal elastic - plastic model for filling materials and strain softening model for ore and rocks were applicable to skarn deposits. Stope stabilities displayed differently under conditions of different mining disturbances and back spans. The maximum principle stress, minimum principle stress, plastic zones and roof settlements met the safety requirements when stope width was less than 36m along the strike. Additionally, the optimized stope structural parameters were proved safe and economi- cally by in situ operations. The optimized alternative involved 36m stope width, wherein room width was 31 m and pillar width was 5m.