【摘要】 采用正交试验分析再生粗骨料、聚丙烯纤维和引气减水剂掺量对再生混凝土抗冻耐久性的影响,结果表明,引气减水剂是影响抗冻性能的重要因素。再生粗骨料掺量70%、聚丙烯纤维掺量0.7kg/m3、引气减水剂掺量0.6%的配合比,可使设计强度为C30的再生混凝土达到F250以上的抗冻等级。提出将饱和面干吸水增长率作为评判再生混凝土抗冻性能的技术指标,它与相对动弹性模量一样,可以反应再生混凝土受冻融破坏的程度。更多还原

【Abstract】 Effect of reclaimed coarse aggregate,polypropylene fiber and air entraining and water-reducing agent adding amount on frost resistance durability of reclaimed aggregate concrete (RAC)is analyzed by orthogonal experiment. The results indicate that air entraining and water-reducing agent is an important factor affecting the frost resistance. The mixing proportion of 70% reclaimed coarse aggregate,0.7 kg/m3 polypropylene fiber and 0.6% air entraining and water-reducing agent can make design strength C30 RAC reach to frost resistance degree over F250. It is suggested to take the saturated surface dry water absorption growth rate as technical index in judgment on reclaimed concrete frost resistance which can reflect the degree of freezing-thawing resistance of concrete as relative dynamic modulus of elasticity,weight loss rate and strength loss rate.更多还原