上向进路充填采矿法不同接顶率充填体的稳定性

Stability of Filling Materials with Different Roof-contacted Filling Ratios in Upward Filling Stoping Method

基于充填料浆采场流动规律和分级尾砂充填进路终态,研究了上向进路充填采矿法不同接顶率充填体的稳定性。将充填料浆采场流动分为不受限沉积扩散和受限向上堆积两个过程,结合充填料浆采场充填终态,从50%充填接顶率开始,按5%递增梯度构建不同充填接顶率的充填体三维模型,运用MIDAS/GTS有限元软件模拟分析不同接顶率充填体受力状况,提出了考虑抗拉、抗压安全系数和拉应力、压应力集中区域体积的综合安全系数方法,用于评价充填体的稳定性。以某矿山为例的评价结果表明,对于二步进路采场开采,一步进路采场充填体的接顶率和综合安全系数越大,其稳定性越高;当接顶率不足75%时,抗拉、抗压安全系数大于1,综合安全系数小于1,充填体有失稳风险;而当接顶率大于75%时,抗拉、抗压安全系数和综合安全系数均大于1,充填体处于稳定状态,其稳定性满足安全生产要求。

Based on the filling-slurry flowing law and final filling state in the stope, this paper analyzes the stability of filling materials with different roof-contacted filling ratios during the upward filling process. The process was divided into two parts： unlimited diffusion deposition and limited upward stacking. Combined with the final filling state, and beginning with 50% roof-contacted filling ratio, 11 filling models were built with an increasing gradient of 5%. The MIDAS/GTS finite element software was applied to analyze the stress condition of filling materials which had different roof-contacted filling ratios, and the comprehensive safety coefficient was put forward to evaluate the stability of filling materials, including the tensile coefficient, compressive safety coefficient and area size under concentrated stress. Take a specific stope as an example, when the roof-contacted filling ratio is under 75% in one-step route stope, the filling material still has the possibility of instability, although the tensile and compressive safety coefficients are higher than 1.0 and the comprehensive safety coefficient is under 1.0. When the roof-contacted filling ratio is above 75%, the tensile, compressive and comprehensive safety coefficients are higher than 1.0, the stability of the filling material reaches a safe level.