再生骨料高性能混凝土耐久性能试验研究

本文主要研究不同胶材用量和再生粗细骨料同时取代对再生骨料高性能混凝土抗氯离子渗透、抗碳化、抗冻性能的影响与作用。结果表明:再生骨料高性能混凝土抗渗透性能、抗碳化、抗冻性能良好,56天氯离子迁移系数小于2.0×10^-12m^2/s,电通量小于700C,28天碳化深度小于3.5mm,F300次冻融循环质量损失率小于2.5%,相对动弹模量下降小于80%;胶材的增加(即水胶比的降低)可以提高再生混凝土的抗渗性和抗碳化性能,对抗冻性能影响较小;再生骨料高性能混凝土的抗冻性能宜采用相对动弹模量下降幅度指标进行评价。

Experimental study on durability of high performance regenerated aggregate concrete

This paper mainly studied the influence and effect of different amounts of cementitious material and substituting recycled coarse and fine aggregate on chloride penetration resistance, carbonization resistance and frost resistance of highperformance recycled concrete. The results showed that the permeability, carbonization resistance and freezing resistance of highperformance regenerative concrete were good, the chloride ion migration coefficient at 56 days was less than 2.0 ×10^-12 m^2/s, the electric flux was less than 700 C, the carbonation depth at 28 days was less than 3.5 mm, the mass loss rate of F300 freeze-thaw cycles was less than 2.5%, and the relative moving modulus decreased less than 80%.The increase of cementitious material(i.e.the reduction of water-binder ratio) could improve the impermeability and carbonization resistance of high-performance recycled concrete, which, however, had little effect on the frost resistance. The freezing resistance of high performance regenerated concrete should be evaluated by the relative moving modulus decreasing amplitude index.