预湿陶粒自养护补偿收缩混凝土收缩的试验研究

Experimental Research on Shrinkage of Prewet Ceramisite Self-curing Shrinkage-compensating Concrete

采用预湿粘土质陶粒作为自养护粗集料,以其等体积的取代碎石掺入补偿收缩混凝土中,测试不同龄期的补偿收缩混凝土自由收缩的变化情况。表明在预湿陶粒自养护的作用下,A、B和C三种膨胀剂配制的补偿收缩混凝土在前4d龄期间均会出现不同程度的膨胀,而基准样出现收缩;在5-11d龄期间,补偿收缩混凝土均出现微量收缩,而基准样出现显著收缩;在12-28d龄期间补偿收缩混凝土收缩显著,但收缩量小于基准样;在28-56d龄期间补偿收缩混凝土收缩值与基准样相差无几,甚至低于基准样。

Prewetting clay ceramsite was mixed in shrinkage-compensating concrete as self-curing coarse aggregate replacing gravel with the same volume, the change of self-shrinkage during different times were tested. Results showed that shrinkage-compensating concrete mixed with three kinds expansion agent A, B and C appear different degree of inflation during the first 4 days age, and the benchmark sample A appear contraction with the curing effect of prewetting haydite; Shrinkage-compensating concrete appear trace contraction while the benchmark sample appear significant contraction during the age from 5 days to 11 days; Shrinkage-compensating concrete appear significant shrinkage, however the shrinkage is less than the benchmark sample during the age from 12 days to 28 days; Shrinkage-compensating concrete appear same shrinkage value and even lower than the benchmark during the period between 28 days and 56 days.