Measurement Method of "Three Breakthroughs" of Normal Speed Railway Based on Vehicle-mounted Mobile Measurement Technology.

The "three breakthroughs" data is the most important basic information in the reconstruction and expansion of existing normal speed railways, but traditional methods are single point measurements, mainly relying on RTK. Its disadvantages includes slow measurement speed and poor continuity of results, which seriously restrict the progress of the project. To improve measurement efficiency, a "three breakthroughs" workflow was designed based on high-precision and high-efficiency vehicle-mounted mobile measurement technology, including job preparation, data collection, data calculation, and thematic information extraction. Moreover, each link of the homework process was elaborated in detail, and a complete and efficient "three breakthroughs" detection technology scheme was constructed. At the same time, a refined elevation anomaly fitting model for elevation correction of mobile measurement POS trajectory lines was proposed, optimizing the accuracy of elevation measurement. Research shows that the measurement efficiency of the "three breakthroughs" detection method proposed in this paper can reach 30 km/h, and the measurement error in the plane direction is 12 mm. After using the refined elevation anomaly value fitting model, the elevation measurement error is reduced from 30.1 mm to 21.5 mm. The research results indicate that the "three breakthroughs" measurement results obtained based on railway vehicle-mounted mobile measurement technology can meet the measurement accuracy requirements of general speed railways. Compared to traditional methods, the measurement efficiency has significantly improved. [ABSTRACT FROM AUTHOR]