Research Commentary on Durability of External Prestressed Segmental Bridges

The design principle of bridges has developed from the safety and economy to the whole balanced consideration of safety, economy and durability. The durability consideration mainly goes to the corrosion problem of prestressing tendons. Traditional internal prestressing tendons need high performance concrete to prevent corrosion materials from outside. Externally prestressed concrete bridge structures proved to be a simple and effective method to improve the durability of prestressed concrete structures. The combination of this technology with the precast segmental construction even improves the durability, and makes structures more advantageous when considering the economy in the whole life-span of structures.