Due to the structure requirements and maintenance requirements of bridge safety, applicability and durability, the construction requirements of the bridge structure compared with other building structure has the following characteristics: can not be repeated, can not fully load test, complex environment, extreme, long service life, restricting factors, the large amount of. Because of these special requirements, the composite material can have a better application prospect in bridge engineering.

1. Fast erection

Can greatly accelerate the construction speed of the composite bridge system, applied to the overpass, bridge, center city district traffic Remote Bridge and the bridge renovation will have a very good economic and social benefits. At the same time, it also has an important application prospect in improving emergency response ability and rapid response ability after disaster.

2. Strong corrosion resistance

The fibers and matrix materials that make up composite materials are all non-metallic materials which are corrosion-resistant. The application of structures can avoid all kinds of hazards and losses caused by corrosion and destruction. The corrosion and deterioration of the traditional structure is very serious, which not only affects the normal use and life of the bridge, but also causes a large number of safety and accident hidden dangers. The corrosion resistance of composite bridge can ensure its long-term reliability. On the one hand, it can improve the safety performance of the structure, and on the other hand, it can reduce the investment in maintenance and operation. And the composite material has the characteristics of bright and lasting color, and it does not need special maintenance. It is suitable for the construction of landscape bridge.

3. Anti overload and anti fatigue

The design of bridge structure in the traditional ductility and deformation ability to obtain a part of security reserve structure, and the mechanical properties of the composites is linear elastic, mainly depends on the bearing capacity of the safety, high practical bearing capacity of composite bridge design reasonable than traditional material bridges. At the same time, the composite material will not undergo plastic deformation before unloading. Therefore, even if the composite material is overloaded, it can also resume its original state, and has little effect on its continued use. In addition, the fatigue resistance of the composite material is far superior to the traditional structural material, which is very suitable for the bridge structure bearing dynamic load. Because of the characteristics of composite bridge, it can improve the adaptability of transportation system, and is of great significance for our current practical application and development.

4. Good seismic performance

Due to the superior mechanical properties of composite materials, the size of members can be reduced, the self weight of superstructure will be reduced, and the inertial force in earthquakes can be reduced, so it is more favorable for earthquake resistance. At the same time, the seismic capacity of the composite bridge is further improved because of the large capacity of the bearing capacity. In addition, because of its light weight, it has significant advantages in rapid restoration and reconstruction after the earthquake, especially in the case of inconvenient traffic. Therefore, the advantages of composite bridge in seismic area are more significant.

5. A larger span can be achieved

The super long span bridge is one of the needs of human progress and economic development. Because steel and concrete have greater self weight and limited strength, the influence of self weight will increase with the increase of span. The traditional structure and materials will be difficult to meet the needs of larger span. Because of its advantages of high strength, light quality and corrosion resistance, FRP is considered as an ideal material for realizing large span structure. Although at present, it is only in the research stage, but the super long span bridge will be the important development direction of the FRP bridge. The development and application of the conventional FRP bridge is the foundation of the super long span FRP bridge.