氟石膏对地坪垫层混凝土补偿收缩性能的影响研究

Study on the shrinkage compensating performance of fluorgypsum to the base floor concrete

采用工业氟石膏与水泥相互作用,引入钙钒石体系对地坪垫层混凝土的收缩性进行研究。结果表明,氟石膏的掺入提高了混凝土的早期和后期强度,对混凝土的收缩有抑制作用;氟石膏掺量为水泥质量的5%时,混凝土的28 d收缩率为214×10^(-6),较未掺时降低了60%;减缩剂对抑制地坪垫层混凝土收缩的效果不明显。XRD和SEM分析显示,水化产物中有大量钙钒石生成;孔结构分析显示,掺氟石膏的混凝土中主要以<0.05 mm的微孔为主。工程应用表明,氟石膏的补偿收缩作用可有效控制地坪垫层混凝土的收缩。

In this paper,the shrinkage of base floor concreteis studied by using the interaction of industrial fluor gypsum and cement to introduce the Ettringite system.The results show that the addition of fluor gypsum can promote the early and late strength of concrete and restrain the shrinkage of concrete.When the content of fluor gypsum reaches 5%of the cement content,the shrinkage of base floor concrete on the 28 day is 214×10^(-6),and the shrinkage of base floor concrete is reduced by 60%.The shrinkage reducing agent has no obvious effect on the shrinkage of base floor concrete.XRD and SEM analysis showed that there are a lot of Ettringite in the hydration products.The pore structure analysis shows that the distribution of holes in the base floor concrete with fluor gypsum is mainly small holes below 0.05 mm.Engineering application shows that shrinkage compensation can effectively control the shrinkage of base floor concrete.