Steam curing is a commonly used method of concrete curing that accelerates the hardening process of concrete and improves early strength by supplying steam to concrete components. This method is widely used in the production of prefabricated components, bridge construction, tunnel construction and other fields. In this paper, taking Wuxi-Jiangyin Intercity Rail Transit Line S1 as the research object, the influence of heat hydration on the gravitational field distribution of short-line prefabricated segmental beams under steam curing was studied by finite element simulation, and the precautions in the process of steam curing were analyzed. The results show that the temperature change results of the components under the finite element simulation are basically consistent with the actual law, the stress changes of the concrete in the steam curing process are within the safe range, and there is no risk of cracking in the concrete during the steam curing process, so the steam curing method is suitable for the maintenance of short-line prefabricated segmental beams.