Accuracy Analysis of Prism-Free Total Station in the Reconstruction and Extension of Expressway

In the process of reconstruction and expansion of expressway, there are high-speed vehicles in the measuring environment, and the danger coefficient measured by ordinary prism total station instrument is too high. Therefore, the prism-free total station instrument has obvious advantages, with high accuracy, but also greatly guarantees the safety of surveyors. In this paper, the prism total station and prism-free total station are used to measure the reconstruction and expansion of expressway. The plane and elevation data are analyzed based on the actual measured data, and the prism-free total station is evaluated by the analysis results. Through research, analysis and verification, the elevation measurement of expressway reconstruction and expansion using prism-free total station instrument is fully in line with the measurement accuracy requirements.