金川Ⅲ矿区破碎站硐室施工变形监测与优化控制

Deformation Monitoring and Optimal Control During Chamber Construction in Broken Station of Jinchuan No.3 Mine

为了有效控制金川Ⅲ矿区1 165 m水平破碎站大断面硐室围岩变形,根据对破碎系统工程的大件道工程围岩变形监测、变形影响因素的分析得出该矿区岩体具有临界蠕变应力低和碎裂剪胀蠕变特征,且变形持续时间长。针对该岩体的变形特点,在破碎站大断面硐室施工中采用"留空让压强支"原则,并提出留空让压强支方案的综合评价指标。设计了3因素4水平的正交数值模拟试验方案,通过综合评价指标的分析确定了合理让压位移量,即毛硐让压变形90 mm,初衬让压变形0,一次支护让压变形50 mm。为了破碎站硐室的安全评价和长期稳定性预测,采用FBG点式光纤光栅传感器监测围岩变形。

To effectively control the deformation of rocks in the large section chamber of broken station in Jinchuan No.3 Mine,we monitored the deformation of surrounding rocks and analyzed the factors affecting such deformation,indicating that the rock mass is characterized by a low critical creep stress,a broken shear dilatation creep,and a long duration of deformation.Aiming at these deformation characteristics,we adopt the principle of ＂yield through leaving space and strengthening support＂ and put forward a comprehensive evaluation index.We also proposed an orthogonal numerical simulation test program among the three factors,designed four levels through the comprehensive evaluation index analysis,and determined a reasonable amount of yield displacement in which the gross distortion of the chamber is 90 mm,the initial lining to yield deformation is 0,and the twain support to yield deformation is 50 mm.For the safety assessment and the long term stability prediction of broken surrounding rocks,we use FBG sensors to monitor the rock deformation.