多公共点传递短边方位的方法研究与应用

隧道洞内导线控制网的短边引起较大的方位误差，将影响隧道贯通精度。对此，介绍采用5~7个公共棱镜侧方边角交会构成的线状网代替导线短边、整体传递控制网坐标、方位的方法，避免了仪器、棱镜的对点误差对方位传递的不利影响；采用角度、距离方差分量估计定权以及稳健估计方法平差保证数据处理结果可靠。经模拟试验测试验证，采用多公共点传递20~60 m短距离导线边的方位精度可达2.0"，有效提高了导线短边方位传递的精度与可靠性。

Research and Application of Method for Azimuth Transfer of Short Distance with Multiple Common Points

The short distance in traverse network causes large azimuth error which will impact the tunnel breakthrough accuracy. Herein a method, which used a linear network made up of joint 5~7 common side square corners of prism instead of the short distance in traverse to transfer as a whole the coordinates and azimuth of network, was introduced, avoiding the undesirable effects on azimuth transfer caused by centering errors of instrument and prism. Moreover, depending on the weight determination from variance component estimation of angle and distance, together with the adjustment from robust estimation, the result of data processing was guaranteed to be reliable. Through the simulation test, it was verified that the azimuth accuracy of multiple common points transfer in 20~60 m traverse might reach 2.0", improving the accuracy and reliability of the azimuth transfer of short distance.