1. Good crack resistance and high rigidity. Due to the application of prestress to the component, greatly delay the occurrence of cracks, under the action of service load, the component can not appear cracks, or delay the occurrence of cracks, so improve the stiffness of the component, increase the durability of the structure.
2. Save materials, reduce the weight. Because the structure must be made of high-strength materials, it can reduce the amount of reinforcement and the cross-sectional size of components, save steel and concrete, reduce the weight of the structure, and has obvious advantages for long-span and heavy-load structures.
3. Can reduce the vertical shear force and the main tensile stress of concrete beam. The curved steel bar ( beam ) of the prestressed concrete beam can reduce the vertical shear force near the support in the beam; And because of the existence of prestressed concrete section, the main tensile stress under load is reduced. This is beneficial to reduce the web thickness of the beam, so that the deadweight of the prestressed concrete beam can be further reduced.
4. Improve the stability of the compression member. When the slenderness ratio of the compression member is large, it is easy to be bent under a certain pressure, so as to lose stability and destroy. If the prestressed concrete column, make the longitudinal stress steel tension is very tight, not only prestressed steel itself is not easy to press bending, but also can help the surrounding concrete to improve the ability to resist bending.
5. Improve the fatigue resistance of the component. Because of the strong prestressed steel bar, in use due to loading or unloading caused by stress change amplitude is relatively small, so can improve the fatigue strength, which is very beneficial to bear dynamic load structure.
6. Prestress can be used as a means to connect structural members to promote the development of new systems and construction methods for large span structures.