The paper gives the calculation formula of the steel box beam rib plate, side line length and coordinate of transition curve sections combined with construction practice.

The cast-in-place concrete Fabricated Hollow-ribbed floor is composed by the reinforced concrete beam, the rib beam and the hollow box.

According to the cracks occurred in the rc box-rib arch Bridge, reinforced the structures with some general Reinforcing Techniques, analysed and researched the mechanism.