厚煤层留窄煤柱沿空掘巷锚网联合支护设计

Design of Bolt-Mesh Support for Gob-Side Entry Driving Beside Narrow Pillar in Thick Coal Seam

为解决寸草塔二矿31201进风巷沿空掘进片帮严重的问题,基于理论分析和计算,给出了合理的煤柱宽度,提出了顶板采用"螺纹钢锚杆+焊接钢筋网片+锚索+π型钢带"、采空区侧巷帮采用"螺纹钢锚杆+焊接钢筋网片"、煤壁侧巷帮采用"玻璃钢锚杆+双层高强度双抗塑料网片"的锚网联合支护方案。并利用FLAC3D数值模拟软件对31201进风巷地质条件及支护方案进行了模拟,模拟结果显示:采用该支护方案巷道顶板下沉量和两帮移近量均较小,可忽略不计,且巷道两帮水平应力为负,表明巷道表面的煤不受拉应力,不存在片帮的倾向。现场试验表明,巷道均未出现片帮现象,且巷道变形量不大。

Aiming at the serious rib spalling in 31201 air income gateway of Cuncaota No. 2 Coal Mine, based on theoretical analysis and calculation, the reasonable width of coal pillar was determined, the bolt - mesh support design was proposed, with ＂deformed steel bar bolt ＋ welded steel grid ＋ anchor ＋ steel band for roof support, and ＂deformed steel bar bolt ＋ welded steel grid＂, ＂solid coal wall： GFRP bolt ＋ double high strength resistant plastic mesh＂ for gob side wall. FLAC3D was used to simulate the geological conditions and verify the support effect. The result shows that, roof subsidence and two -side displacement are small enough to be ignored, the horizontal stress is under zero, indicating no tensile stress on the rib coal and no rib spalling tendency. The result was proved in field test, with no rib spalling, and small roadway deformation.