建下散体材料充填开采方法实践研究

Practical Study on Backfilling Mining Method with Granular Materials under Buildings

摘要: 为了安全经济的回收建下遗留条带煤柱，结合当地资源赋存状态，采用矸石、建筑垃圾、粉煤灰为主要材料进行无胶结散体材料充填。通过散体充填材料压实试验获得了不同配比条件下力学特性及最优配比：设计矸石、建筑垃圾与粉煤灰的质量之比为1:1:0.4。进一步地，设计了一种以矸石、建筑垃圾、粉煤灰为主要材料的充填系统及充填步骤。采用试验获得的优化后的散体充填材料进行工业性试验，实测地表累计最大下沉量为20 mm、最大水平变形为1.3 mm/m，地表沉陷得到有效控制。

Abstract: To safely and economically recover the residual strip coal pillars under buildings, combined with the local resource occurrence status, uncemented granular materials (mainly composed of gangue, construction waste, and fly ash) were used for backfilling. Through compaction tests on the granular backfilling materials, the mechanical properties under different mix ratios and the optimal mix ratio were obtained: the mass ratio of gangue, construction waste, and fly ash was designed as 1:1:0.4. Furthermore, a backfilling system and corresponding backfilling procedures using the above three materials as the main components were designed. Industrial tests were conducted with the optimized granular backfilling materials obtained from the tests. The measured results show that the maximum cumulative surface subsidence is 20 mm and the maximum horizontal deformation is 1.3 mm/m, indicating that surface subsidence has been effectively controlled.