Experiment study on drying shrinkage deformation of recycled aggregate concrete

Drying shrinkage deformation is one of the most important reasons which causes cracking of concrete materials. Mix design of C30 natural aggregate concrete(NAC) is used as reference, the experiment of drying shrinkage considering the influence of recycled aggregate replacement ratio and mixing amount of fly ash, water reducer, and expansive agent was made. The results show that: In the case of fixed amount of mixing water and cement content, the addition of water reducing agent and recycled aggregate increase the shrinkage deformation of recycled aggregate concrete(RAC); to a certain extent, the addition of fly ash can inhibit the shrinkage deformation of RAC; with the addition of expansive agent, the shrinkage deformation of RAC significantly reduce, and this inhibitory effect is stronger than fly ash´s.