钟九铁矿-550 m 水平大断面交岔点支护—注浆加固耦合技术方案

钟九铁矿正进行-550 m 水平一期井巷开拓工程建设,为保障巷道安全掘进及临时支护的有效性,针对 -550 m 水平 6^#交岔点断面大、围岩破碎、裂隙发育的现状,提出了锚网喷+锚索联合支护及深浅孔—高低压耦合注浆加固的巷道围岩稳定性防控技术方案。在注浆加固过程中,首先利用浅孔—低压注浆技术将破碎围岩内的裂隙充填密实,使巷道周边围岩具有一定的抗压能力,提高深部围岩浆液的可注性;然后采用深孔—高压注浆技术将巷道顶板上部破碎围岩与稳固岩层形成整体结构,进一步提高支护体系的稳固性。利用理论计算与数值模拟相结合的方法确定了其支护参数,分析了注浆加固关键技术及施工工艺流程,实践成效显著,为后续大断面交岔点安全施工提供了技术支持。

Coupling Technical Scheme of Supporting-Grouting Reinforcement for the Intersection of the -550 m Level Horizontal Large Section in Zhongjiu Iron Mine

The phase Ⅰ well lane open-out prolongation is building for -550 m level in Zhongjiu Iron Mine,in order to ensure the safety of roadway excavation and the effectiveness of temporary support,in view of the current situation of large section,broken surrounding rock and developed cracks for 6^# intersection at the -550 m level,the technical scheme of roadway surrounding rock stability prevention and control was put forward,which includes the combined support of anchor shotcrete-bolt + anchor cable and the reinforcement of deep and shallow borehole-high and low pressure coupled grouting. During the process of grouting reinforcement,firstly,the shallow pore-low pressure grouting technical was adopted to fill the cracks in the broken surrounding rock and compactness,so that the surrounding rock of the roadway has a certain pressure resistance ability,and the grouting ability of the deep surrounding rock was improved. Then,the deep hole and high pressure grouting technical was used to form the overall structure of the broken surrounding rock and the stable rock strata in the upper part of the roadway roof, which further improves the stability of the support system. Based on the method of theoretical calculation and numerical simulation,the supporting parameters were determined,and the the key technology and construction process of grouting reinforcement were analyzed. The practical effect is remarkable,which provides technical support for the subsequent safe construction of large section bifurcation points.