引气轻集料混凝土工作性和力学性能的研究

为配制高性能轻集料混凝土,研究了优质引气剂对大流动性轻集料混凝土的工作性及力学性能的影响规律.研究表明:引气剂对大流动性轻集料混凝土的坍落度的影响不大,对黏度影响较大;引气可减少离析、泌水及坍落度损失,明显改善轻集料混凝土拌合物的工作性能;一定范围内,引气对轻集料混凝土的力学性能有益;含气量小于5.5%时,抗压强度未降低,而是有所提高,提高幅度约3%～4%;含气量小于5.5%时,抗折强度提高,提高幅度约8%～10%.

Study on workability and mechanical preperties strength of air-entrained light-weight aggregate concrete

To make high performance lightweight aggregate concrete, the influence of air-entrained agent on workability and mechanical preperties of large slump light-weight aggregate concrete is studied in this paper. The results show that the effect of air-entrained agent on large slump of fresh lightweight aggregate concrete is slight and effect on viscosity is distinct. The segregation and bleeding induced and the slump loss decrease when air bubble is entrained into concrete. Air-entrained agent can distinctly improve workability of fresh light-weight aggregate concrete. Air-entraining is benefit to mechanical property of hardened lightweight aggregate concrete within a suitable range of air content. Air-entraining can increase compressive strength about 3% -4% when air content is less than 5. 5 percent. At the same time, with the increasing of air content (less than 5.5%) , flexural strength increases about 8% ~ 10% .