In order to ensure the safety of taking the high-speed rail. When high-speed trains run at high speed, the requirements for lines and vehicles are very high. If the speed is too fast, it will pose a certain threat to the safety of train operation. Therefore, moderately reducing the speed of high-speed rail can effectively reduce the risk of accidents and enhance passengers' sense of travel safety.

Considering the carrying capacity of cities along the way. There are many towns between Tianjin and Baoding, and there are many tourist attractions and residential areas along the way. If the high-speed rail is too fast, it will shorten the pit stop time, increase the difficulty and pressure of getting on and off, and bring unnecessary burden to cities along the way. If the speed of high-speed rail is properly reduced, it can better connect with urban traffic and balance the carrying capacity of various places.

Environmental factors are also a consideration. There may be complex geographical conditions or environmental protection zones in the area where the high-speed rail line passes. Too fast train speed may cause interference or influence to the surrounding natural environment. In order to avoid damaging the ecological environment, it is reasonable to reduce the speed of high-speed rail.

Economic factors are also one of the important factors affecting the speed design of high-speed rail. The construction and operation of high-speed rail need to invest a lot of money, and the speed has a certain relationship with the cost. If the speed is raised to the limit, it may cause greater pressure on finance. Properly reducing the speed can control the construction and operation costs to a certain extent, and better balance the economic and social benefits.

There are many reasons for the slow design speed of Tianjin-Baoding high-speed railway. In order to ensure the safety of passengers, reduce the burden of cities along the way, protect the environment, and better balance economic and social benefits, a comprehensive balance has been carried out. The high-speed rail designed in this way can better meet the needs of all aspects and ensure passengers to travel comfortably and safely.