用不同粗骨料(石灰石碎石、再生粗骨料)、细骨料(河砂、人工砂、再生细骨料)两两相组合,共配制6组高性能混凝土进行对比试验,测试抗压强度、弹性模量、收缩和徐变4个性能指标并进行显著性分析。结果表明,骨料类型对高性能混凝土抗压强度的影响不明显,但对弹性模量、收缩和徐变性能都有显著影响。粗骨料对弹性模量和收缩性能的影响较为显著,细骨料对徐变的影响较为显著。再生粗骨料混凝土收缩、徐变早期发展较慢,而中后期的发展速度明显快于普通混凝土;再生细骨料混凝土收缩、徐变的发展速度始终远快于普通混凝土。在此基础上,提出了考虑粗、细骨料类型和骨料种类的高性能混凝土收缩和徐变的预测模型。
Six groups of high performance concrete ( HPC), with different combinations of two coarse aggregates (crushed limestone, recycled coarse aggregate) and three fine aggregates (river sand, manufactured sand, recycled fine aggregate) were prepared for a comparison test of their compressive strength, elastic modulus, shrinkage and creep performance. The result shows that the aggregate type has no obvious influence on strength of HPC, but affects elastic modulus, shrinkage and creep significantly. The coarse aggregates have stronger effect on elastic modulus and shrinkage, and the fine aggregate affects creep more significantly. The development of shrinkage and creep of recycled coarse aggregate concrete is slower in early stage, but becomes obviously faster than normal aggregate concrete in the middle and later stage. In contrast, the development speed of shrinkage and creep of fine aggregate concrete is always much faster than normal concrete. On this base, prediction models of shrinkage and creep of HPC, considering coarse and fine aggregate type and kinds of aggregate, are proposed by regression analysis.