【摘要】 针对海洋环境条件,重点研究了硅灰混凝土的抗冻性和氯离子扩散性能的关系。试验分析了水胶比、硅灰等量替代水泥掺量大小、引气剂掺量等因素对混凝土抗冻性和氯离子扩散性能的影响,并与普通混凝土进行了对比。结果表明,掺加硅灰不能提高混凝土的抗冻性但可提高混凝土的抗氯离子渗透性;硅灰只有与引气剂共同使用,才能同时提高混凝土的抗冻性和抗氯离子渗透性能;硅灰掺量在10%左右对混凝土的抗冻和抗氯离子渗透综合性能影响存在一个最佳值。为评估混凝土的抗冻性和抗氯离子渗透性的综合性能,提出了新的评价方法——冻渗比(R值方法),并进行了试验验证。更多还原

【Abstract】 The properties of silica fume concrete in natural sea water are studied,with special focus on the relationship between the freeze-thaw durability and chloride ion diffusion coefficients.The influence of various factors on concrete resistance to frost and chloride diffusion is studied,including the water-cement ratio,equivalent silica fume dosage substitution for cement,and the amount of air-entraining agent and compared with that of ordinary concrete.The results show that adding silica fume cannot improve the frost resistance of concrete but it increases resistance to chloride diffusion.Both the frost resistance and chloride diffusion properties can be improved simultaneously when silica fume is used with an air-entraining agent.A silica fume content of approximately 10% is the optimum value for the composite resistance to frost and chloride diffusion.A new assessment method(R-value method) is proposed to evaluate the composite properties of frost resistance and chloride diffusion of marine concrete.更多还原