The Precast beam is a kind of concrete beam component which is poured in the concrete component factory according to the design requirements of Engineering drawings. When the strength reaches the design requirements, it is transported to the installation location of the engineering site for installation. Prefabricated beams mainly include prefabricated concrete beams, prefabricated concrete bridges and other prefabricated concrete bridges are mostly pre-stressed components. The main features are that it can produce in batches ahead of time, install quickly and shorten the construction period.