再生粗骨料混凝土抗冻性试验研究

摘要

再生混凝土的研究与应用对于保护环境具有重大意义,其耐久性则是影响生产应用的重要指标.重点研究了再生粗骨料取代量、矿物掺和料等因素对再生混凝土抗冻性的影响.结果表明：再生粗骨料混凝土的质量损失率均满足5%的试验要求,且质量损失率随着再生骨料取代率的增加而下降;再生粗骨料混凝土的相对动弹模量低于天然骨料混凝土,达到了冻融循环抵抗性指标,满足抗冻性要求;掺普通矿粉的再生混凝土比掺粉煤灰的再生混凝土抗冻性好;硅灰对提高再生混凝土（掺粉煤灰）的抗冻性有明显作用.%The research and application of recycled concrete are of great significance for environmental protection and its durability is an important index of production and application.The influences of the replacement rate of recycled coarse aggregate,mineral admixture and other factors on the frost resistance of recycled concrete are studied in this paper.The experimental results show that the mass loss rate of recycled coarse aggregate concrete meets the experimental requirement by 5% and it descends along with the increase of the replacement rate of the recycled fine aggregate.The relative dynamic modulus of recycled coarse aggregate concrete is inferior to that of the natural aggregate concrete,but it reaches the freeze-thawing circulation norm and meets frost resistance requirements.The frost resistance of the recycled aggregate concrete with mineral powder is better than that of the recycled aggregate concrete with fly ash.The silicon ash can enhance the frost resistance of the recycled concrete（with fly ash） significantly.