摘要
Abstract
In order to improve the mechanical and durability of recycled concrete,recycled concrete samples with different mineral admixtures were prepared to systematically study the changes in compressive strength,chloride ion penetration resistance and relative dynamic elastic mod-ulus of recycled concrete with different mineral admixtures,and the mechanism was analyzed in combination with mercury injection test.The results show that the mechanical and durability of concrete can be significantly improved by adding proper amount of mineral admixtures.The optimum dosage of fly ash,mineral powder and silica fume is 10%,20%and 6%respectively,and the improvement effect of silica fume is the most significant.Compared with the benchmark specimen,the compressive strength of SF6 increased by 21.98%and the chloride ion per-meability coefficient decreased by 41.62%at 90 days.At 28 d,the relative dynamic elastic modulus of SF6 increased by 28.35%and the to-tal porosity decreased by 26.80%.The results show that the active silica of silica fume reacts with the hydration products of cement to generate more gel material,optimize the internal pore structure of concrete,and improve the overall performance of recycled concrete.关键词
再生混凝土/矿物掺合料/力学性能/耐久性能/微观分析Key words
Recycled concrete/Mineral admixture/Mechanical properties/Durability/Microanalysis分类
建筑与水利
