桥梁混凝土耐久性设计

Design of Bridge Concrete Durability

桥梁所处的环境一般比较恶劣 ,各国工程经验证明 ,桥梁损坏是比较严重的 ,其修复要耗费大量资金 ,大于新建桥梁时适当提高有关技术要求所增加的费用。在大桥新建时 ,我们就应该重视桥梁混凝土耐久性设计 ,应用高性能混凝土。从材料选择、集料碱活性、外加剂与耐久性、大体积混凝土防止开裂、密集钢筋部位应用高流动性混凝土或自密实混凝土以及桥面混凝土等都应从耐久性及影响耐久性的施工性能等方面加以校核 ,以保证桥梁在使用环境下安全地工作 10 0年。

Bridges are always located in severe environment.Experiences from the engineerings in many countries prove that bridge destructions are serious and their repairs need a lot of money more than the increased money requred by properly raising the related technical standards of new bridges under construction. During building the bridge, we should pay more attention to the design of concrete durability and use the high performance concrete.Material selection, alkali aggregate reactivity,durability of admixture, preventing crack of mass concrete, application of free flowing concrete or self dense concrete to the place with close steel bars and bridge deck concrete etc. should be checked on durability and construction performance effecting durability in order to improve and extend the service life of bridge for one hundred years.