精准测量点位控制隧道超欠挖技术

The Accurate Measuring Point Position Controlling Tunnel Ultra or Owe Digging Technical Practice

通过对花博山2号隧道超欠挖问题的研究,发现其存在的主要影响因素是测量放样点位随意问题。对传统测量放样法进行改进,提出以设计轮廓图上主要曲线控制点为测量放样点,精确计算其点位坐标,必要时引进辅助控制点,从而减少了人为主观因素,提高了描绘与设计轮廓线的吻合度。实践表明,光面爆破效果达到预期,使开挖轮廓一次成型,有效地控制了隧道的超欠挖。

Accurate positioning method to control over or insufficient excavation for tunnels investigation to Huaboshan No. 2 Tunnel shows that random selection of lofting control point caused the over or insufficient excavation. The authors improved the traditional lofting method by proposing that the main curve control points in the design outline should be used as lofting control points. Their coordinates should be accurately calculated and auxiliary points should be used if necessary. The method adopted minimized the influence of subjective factors and improved the accuracy. Practice shows that smooth blasting effect was achieved and ultra or insufficient excavation was under control.