陀螺全站仪在复杂山区特长隧道定向中的应用研究

Research on Application of Gyro Total Station in Orientation of Extra-long Tunnel in Complex Mountainous Area

为解决复杂艰难山区特长隧道陀螺定向测量作业时仪器搬运难度大、劳动强度高等难题,对传统陀螺定向作业和计算方法进行优化。外业采用自由设站法,在待测边一定范围内任意位置设站,分别对两个控制点进行陀螺定向测量和边角测量;内业中,计算陀螺方位角和坐标方位角并进行精度评定,依据地下陀螺边和导线边方位中误差取权,并将加权平均值融入导线网进行联合平差。研究表明,该方法消除了仪器对中误差对定向精度的影响,简化外业操作并有效降低劳动强度和搬站难度,具有设站位置灵活、外业操作简洁、检核条件多、内业计算简单等优点。研究结果表明,案例中自由设站法定向成果用于隧道贯通测量,横向贯通误差8.2 mm,优于同等条件下传统作业法横向贯通误差(14.3 mm),证明自由设站法定向方位准确、精度较好。

In order to improve instruments moving efficiency and reduce labor intensity in the gyro orientation measurement of extra-long tunnels in complex mountainous areas,traditional operation and calculation method were optimized.During the field survey,free station measurement was adopted,and the gyro total station was set up at position within a certain range to carry out the measurement of gyro orientation and length-angle measurement on two control points respectively.After the survey,the gyro azimuth and coordinate azimuth were calculated and the accuracy was evaluated.The weighted average value was integrated into the gyro azimuth and traverse side of the ground for adjustment.The study shows that the method eliminates the influence of the instrument alignment error on the orientation accuracy,simplifies the field operation,reduces the labor intensity and the difficulty of moving the station.The method has advantages including flexible station location,simple field operation,various checking conditions and simple calculation for internal operation.In the case presented,the free station method was applied to a tunnel breakthrough gyro orientation measurement,the lateral error was 8.2 mm which was better than that traditional measurement(14.3 mm)under same conditions.It is proved that,with free station measurement method,the orientation azimuth was correct and the accuracy was precise for the gyro orientation measurement.