白芨沟煤矿波形钢腹板支架支护的数值分析及现场监测

    Numerical simulation analysis and field monitoring of support with steel corrugated webs in Baijigou Coal Mine

    • 摘要: 白芨沟煤矿南翼采区特厚煤层回采巷道中,由于11#矿用工字钢支架变形过大,支护强度不够,为提高巷道的稳定性,提出采用高强钢材的波形钢腹板支架进行支护,该支架由波形钢腹板棚梁和焊接工字钢棚腿组成。结合巷道开挖的数值模拟,分析了无支护、矿用工字钢和波形钢腹板支架三种支护条件下巷道围岩变形和应力变化情况,并在白芨沟煤矿运输顺槽巷选择试验段采用波形钢支架单棚置换矿用工字钢对棚,对波形钢腹板支架进行了现场变形和支护反力监测。计算结果表明,无支护时,巷道顶部竖向变形达到243 mm,两帮位移变形达到114 mm,架设11#矿用工字钢和波形钢腹板支架后,竖向变形依次减小至约60.0 mm和25.5 mm,两帮变形依次减小至56 mm和28 mm,波形钢腹板支架支护效果明显优于11#矿用工字钢支架。现场监测结果表明,巷道掘进期间波形钢腹板支架顶底收敛量比矿用工字钢棚梁平均减少了约54%,两帮的收敛量比矿用工字钢棚腿平均减少了约80%,压力盒监测到波形钢腹板支架上的支护反力在小范围内波动,最大支护反力为2.6 MPa。

       

      Abstract: Since excessive deformation of the No.11 mining I-beam supports and insufficiency of support strength in the thick coal seam mining roadway of the southern wing of Baijigou Coal Mine, support with steel corrugated web of high strength steel is proposed for support to improve the stability of the roadway, which is composed of steel corrugated web beams and welded I-steel legs. Based on the numerical simulations of roadway excavation, deformation and stress developments of surrounding rock are analyzed under three support conditions, such as unsupported, supported by mining I-beam, and supported by steel corrugated web. In the transportation entry roadway of Baijigou Coal Mine, a test section is selected to replace the double-shed mining I-beam supports with a single shed of steel corrugated web support. Field deformation and support reaction monitoring are conducted on the steel corrugated web support. The results show that without any support, the vertical deformation of the roadway roof reaches 243 mm and the convergence of the two sides of the roadway reaches 114 mm. After installing No.11 mining I-beam supports and supports with steel corrugated web, the vertical deformation decreases to about 60.0 mm and 25.5 mm and the convergence of two sides also decrease to 56 mm and 28 mm, respectively. The support effect of the supports with corrugated webs is significantly better than that of No.11 mining I-beam support. Field monitoring results show that the mid-span convergence of corrugated web beam decrease by 54% compare to I-beams, and the convergence of welded I-steel legs decrease by 80% on average compare to mining I-shaped legs. Support reaction forces detected on corrugated web supports fluctuate within a small range, with a maximum reaction of 2.6 MPa.

       

    /

    返回文章
    返回