基于不同岩层组合对底板阻水效应的流固耦合机理研究

为了探究不同岩层组合底板对承压水的阻隔效果，以淮北矿区下组煤底板为研究 对象，建立了三种不同组合特征底板模型。基于FISH语言对FLAC3D软件进行二次开发， 对流固耦合条件下不同组合特征底板采动应力及围岩渗透性进行了综合分析。结果表明 :流固耦合条件下，底板采后应力转换点深度较不考虑底板水压条件下加深，且底板深 部出现了明显的卸压现象；硬软型底板采后卸荷程度及应力转换点降幅最大，而软硬相 间型底板受最小；硬软型底板采后渗透性提高4.5倍，而软硬相间型底板仅提高1.4倍， 研究结果揭示出软硬相间岩层组合底板阻水效果最好，而硬软型底板最差。

Study on fluid-solid coupling mechanism for water resistance effect of coal floor based on different combination of rock strata

To investigate the resistance effect of coal floor with different combination of rock strata on confined water, taking the coal floor of lower coal group in Huaibei mining area as research object, three coal floor models with different combination characteristics were established. The secondary development was conducted on FLAC3D software based on FISH language, then the comprehensive analysis on the mining stress of coal floor and the permeability of surrounding rock with different combination characteristics under the condition of fluid-solid coupling was carried out. The results showed that under the condition of fluid-solid coupling, the depth of stress transition point for coal floor after mining was larger than that without considering the condition of floor water pressure, and the obvious pressure relief phenomenon appeared in the deep floor. The decreasing amplitude of unloading degree and stress transition point for hard-soft type coal floor after mining were the largest, while those for alternated soft-hard type coal floor were the smallest. The permeability of hard-soft type coal floor after mining increased by 4.5 times, while that of alternated soft-hard type coal floor increased by 1.5 times only. It revealed that the water resistance effect of coal floor by the combination of alternated soft-hard rock strata is the best, while that by the hard-soft type coal floor is the worst.