公路隧道深大通风竖井导孔纠偏方法研究

Reserch on Rectifying Deilling Deflection Methods of Deep and Large Ventilation Shaft in Highway Tunnel

导孔施工是通风竖井反井施工中的关键部分,针对建金高速公路金华山隧道竖井导孔偏斜过大的现象,引入KXP-2D(S)数字罗盘测斜仪进行不同井深测斜,利用不同井深测斜数据得出竖井最终偏斜率来检验导孔是否合格,对导孔偏斜过大原因进行分析,并提出整治方案、验证整治效果。结果表明:软弱岩层会导致导孔施工偏斜过大,极易造成导孔有效性降低;KXP-2D(S)数字罗盘测斜仪测得竖井导孔中心线最终偏移2.785 m,偏斜方向为东70°方向,与全站仪所测数据仅差0.015 m,偏斜角度相差2°,证明了KXP-2D(S)数字罗盘测斜仪能够较好的在深大竖井偏斜测量中应用;以此提出了一整套填孔注浆、重找孔标、"吊打法"的偏斜整治方法进行竖井偏斜整治,通过工程应用,验证了该方法的适用性,为类似竖井工程提供借鉴。

The drilling construction is a key part of the ventilation shaft construction using raise-boring method.For the excessive deviation of the shaft drilling in the Jinhuashan Tunnel of Jianjin Expressway,the KXP-2 D(S)digital compass inclinometer respectively in pilot hole drilling.Using the final deflection rate of the shaft obtained from the different depth survey data of the shaft to check whether the drilling is qualified.Analyzing the reasons for the excessive deflection of the drilling and propose a remediation plan to verify the remediation effect.The results show that:weak surrounding rock will lead to excessive deflection of the drilling construction and can easily reduce the effectiveness of the drilling;The KXP-2 D(S)digital compass inclinometer measured the final deviation of the centerline of shaft drilling by 2.785 m and the deflection direction was 70°east,which was only 0.015 m away from the data measured by the total station and the deflection angle was 2°,proving that KXP-2 D(S)digital compass inclinometer can be better applied in shaft deflection measurement;A set of deflection rectification methods of filling the drilling with concrete injected、re-finding the center line coordinates of the drilling and"hoisting method"were proposed to remedy the deflection of the shaft.Through engineering application,the applicability of the method is verified,and it can provide reference for similar shaft engineering.