基于3DEC的千米深井筒关键区域稳定性与支护研究

Research on Stability and Supporting for Critical Areas of 1000 Meters Deep Mine Shaft Based on 3DEC

针对姚家山矿千米深井筒易变形和支护困难的现状,利用理论计算和3DEC数值模拟的手段,分析了深井各区段的应力应变分布规律,研究了千米深井筒开挖与支护的稳定性,并对比分析了不同支护方案对井筒稳定性的影响,验证了理论计算得到的井筒围岩位移与数值模拟结果相吻合;得到了井筒支护的4个关键区域：井深30~50 m、55~100 m、630~635 m、1 080~1 090 m区段。确定了井筒最优支护方案：在表土段及基岩风化带喷混凝土强度等级C50,厚度500 mm,井壁环向钢筋配筋率为0.4%;基岩段支护参数混凝土强度等级C50,井壁厚度700 mm,井壁环向配筋率0.15%。研究成果对深部矿井建设中的支护方案选择与围岩控制有参考价值。

According to the current situation of easy deformation and supporting difficulties existing in the kilometer deep well of Yao- jiashan Mine,based on the method of theoretical calculation and 3DEC numerical simulation, the distribution of stress-strain among each section was analyzed, researching the stability of the excavation and lining about kilometer deep well and analyzing the influence of dif- ferent supporting schemes on wellbore stability. Theoretical calculation of the shaft displacement of surrounding rock and the numerical simulation results is verified to be coincided;4 key areas in shaft supporting are obtained ：30 -50 m,55 ~ 100 m,630 ~ 635 m, 1 080 ~ 1 090 m section;the optimal scheme of shaft supporting is determined：to adopt concrete strength grade of C50 in overburden and bed- rock weathering zone,thickness 500 mm,hoop reinforcement ratio is 0. 4% on the wall;to adopt concrete strength grade of C50 in ped- estal rock zone,thickness 700 mm,hoop reinforcement ratio is O. 15% on the wall;the research is instructive to the supporting scheme selection and control of surrounding rock in the construction of deep coal mine.