金山店铁矿玻璃钢锚杆支护试验及存在问题

金山店铁矿矿岩松软破碎，因支护的金属锚杆腐蚀失效较多，巷道变形垮冒严重。玻璃钢锚杆具有抗腐蚀、抗拉强度高等优点，为此采用玻璃钢锚杆替代螺纹钢锚杆进行了支护试验。数值分析表明全长锚固预应力玻璃钢锚杆相比螺纹钢锚杆可以有效改变锚杆中性点位置，改善水泥浆应力分布特征，提高锚杆及水泥浆抵抗围岩向壁面变形的能力。工业试验及试验巷道变形监测表明采用玻璃钢锚杆支护后在控制巷道变形方面可以取得与螺纹钢锚杆相同的巷道变形控制效果；且采用玻璃钢锚杆可以更好控制巷道离层破坏，减少矿岩中硫化物对锚杆的腐蚀，从而提高整体支护可靠性。但玻璃钢锚杆尾部托盘螺母承载力较低，难以抵抗巷道较大变形以及爆破冲击波破坏，还需做进一步研究和改进。

The GFRP Bolt Support Test in Jinshandian Iron Mine and the Existing Problem

The ore and rock mass of Jinshandian Iron Mine is very cracked，the metal bolts supported failure is serious because of corrosion，So the problem of development working failure is serious. Because of the good characteristics of glass fiber reinforced polymer (GFRP) anchor，the paper study of using GFRP bolt supporting to replace screw-thread steel bolt supporting. The paper analyzed the supporting effect of screw thread steel anchor and GFRP anchor under the mining condition based on numerical analysis. The numerical analysis show that using GFRP anchor supporting can effectively change the neutral point position，and can improve the stress distribution characteristics of cable grout，thereby the bolt capacity of resistance to tunnel deformation is improved. Based on the GFRP bolt supporting industrial test and monitoring，the paper analysis the testing tunnels convergence deformation and discusses the GFRP bolt supporting problems in Jinshandian Iron Mine. Experiments show that using GFRP bolt or screw thread steel anchor supporting can achieve the same effect in controlling the deformation of tunnel，but the tail of GFRP bolt destroyed easily under blasting shock effect，and the nut easily shedding under the large tunnel deformation effect. So the GFRP bolt can not continue to provide effective extrusion pressure and the metal net fall off until the entire bolt failure.