What unimaginable difficulties did chengdu-kunming railway overcome during its construction?

The first is to overcome the difficulties in geological exploration. You know, the terrain that chengdu-kunming railway crosses is very complicated. 1952 since the early exploration in the second half of the year, the Ministry of Railways and the Ministry of Geology have mobilized more than 5,000 engineering geological surveyors, completed geological mapping14,800 square kilometers, and drilled 212,700 meters. After many discussions, the route was finally determined.

After the route was determined, after two years' efforts, the route of 1. 1 0,000 kilometers was surveyed and compared, and more than 300 schemes were made for comparison, and the route blueprint was basically drawn. At that time, the scale of survey and design was unprecedented in the history of China railway.

Secondly, due to the technical level at that time, the railway line had to turn left and right to avoid building long tunnels, so it crossed Niuri River 13 times, Anning River 8 times, Longchuan River 47 times and Laozhuang River 16 times, except for Dadu River and Jinsha River twice.

Not only that, but also innovation on the original basis. Through the efforts of the new technology battle group and all road builders, which are directly participated by more than 200 scientific researchers and engineers from all units in China, breakthroughs have been made in four aspects: traction power, communication signals, superstructure of lines, and rapid construction of earth and stone for bridges and tunnels, which has raised the level of railway construction in China to a new level and laid a foundation for the construction of other railways in the future.