清水混凝土抗碳化及氯离子侵蚀性能试验研究

Study on mechanical properties and mix proportion optimization of fair-faced concrete

通过采用大掺量矿物掺合料制备清水混凝土,系统研究了胶凝材料与混凝土龄期对混凝土耐久性能的影响,并对混凝土耐久性能的优劣性进行评价。试验结果表明:在碳化作用的早期(碳化作用28 d以前),不同胶凝材料体系下的清水混凝土抗碳化能力的优劣为C<D<A<B,在碳化作用的后期(碳化作用28 d及以后),不同胶凝材料体系下的清水混凝土抗碳化能力的优劣为D<C<B<A;不同系列清水混凝土在28 d龄期下氯离子渗透系数的大小顺序为:C>D>A>B,到84 d龄期时氯离子渗透系数大小顺序为B>A>D>C。对于地铁等要求使用年限在100年左右的重大工程,清水混凝土可以达到混凝土结构耐久性的要求。

By use of using high volume mineral admixtures of cementitious to making fair-faced concrete,researching the effect of the total amount of cementitious materials and mineral admixtures on the durability of fair-faced concrete systematically.The experimental results show that the carbonization capacity of the concrete under different cementitious materials is C〈D〈A〈B in the early stage of carbonization（before the carbonation is 28 days）.In the later stage of carbonation（after 28 days of carbonation）,the carbonization capacity of face-concrete under different cementitious materials is D〈C〈B〈A.the capacity of resistance to chloride ion corrode of the concrete under different cementitious materials is C〉D〉A〉B when the age of concete is 28 days.The capacity is B〉A〉D〉C when the age of concete is84 days.For the subway and other requirements of the useful life of about 100 years of major projects,fair-faced concrete can meet the durability requirements of concrete structures.