The design speed of general high-speed railway can reach 250-350. Among them, the design speed of 350-based electrified ordinary railways under construction in China has several grades. What I know is: China Railway No.1 Bureau, with a design speed of 200 per hour; China Railway Second Bureau, design speed160; China Railway Third Bureau, design speed 120. Among them, newly built, rebuilt and expanded national trunk railways generally use China. The design speed is not less than 200 per hour, and the important busy lines are reserved for 250. This morning, I saw in Huashang Daily that Xicheng Railway has been approved by the National Development and Reform Commission, and it is built according to the national railway I, with a design speed of 200 kilometers per hour. In the previous paragraph, the design speed of sichuan-tibet railway was also 1,200 kilometers per hour, which sounds very moving. At present, the design speed of the eastern section of Longhai Line in Shaanxi is only 120- 140 km. The western plain section has been rebuilt and expanded many times, and the design speed has reached 160-200 kilometers per hour. Even so, sometimes I can overtake the train in the same direction far from the train station by bike. Please visit Haizi Railway Network for details.