Abstract: A physical model of T-shaped beam made from C50 concrete was provided to investigate the prefabricating process of those types of prestressed beams for a bridge, and a compression test was carried out to it on a press. The results showed that how the transverse stress changes in concrete under an anchor slab. With an FEM model developed, the transverse stress was calculated. Comparing the calculated results with tested ones and fitting them, an empirical formula was given to practically solve the transverse stress under anchor slab. Then, the maximum transverse stress and its position can be found out by extremum method. It is confirmed that in detail design the transverse cracks occurring on beam ends can be efficiently restricted if the concrete beam's periphery 30 cm below the anchor slab is constrained to a certain extent.