辽河特大桥混凝土设计及耐久性研究

Study on Durability and Design of Concrete in Liao River Bridge

对辽河特大桥工程六系列混凝土进行了配合比设计,对各系列混凝土的力学和耐久性进行了系统试验。试验结果表明:提高混凝土耐海水的侵蚀能力,必须提高其抗氯离子渗透性能。采用双掺和三掺矿物掺和料,水胶比低于0.38,胶凝材料总量不少于470kg/m3,可有效降低氯离子扩散系数,提高混凝土抗海水侵蚀能力。采用F ick模型,合理推测出结构达100年使用年限,结构各部位保护层厚度。

The mixture ratios of concrete in six strength grades used in the construction of Liao River Bridge were designed,and the mechanics properties and durability of concrete were tested.The experimental results show that,the chlorion permeability resistance of concrete must be improved in order to improve the ability of marine corrosion resistance of concrete.Two kinds or three kinds of mineral admixture were used in concrete,the water-gelled material ratio was lower than 0.38 and the total amount of gelled material no less than 470kg/m^3.It proves that the method can reduce the coefficient of chlorion diffusion effectively,and improve the ability of marine corrosion resistance of concrete.The thicknesses of the concrete antiabrasion layer in different parts of the construction in the 100 years service life were calculated by using Fick modle.