A review of the mechanical properties of recycled aggregate concrete filled steel tubular column

The difference in mechanical behaviour of the recycled aggregate concrete (RAC) and that of the normal aggregate concrete (NAC) may lead to different mechanical behaviour for the recycled aggregate concrete filled steel tubular (RACFST) columns from traditional CFST columns. In this context, study achievements on the basic mechanical properties of the RAC were presented in this paper. The review of the literatures shows that the mechanical properties of the RACFST columns are similar to the companion CFST columns. Compared to the RAC, the deviation of the mechanical properties of RACFST members is much smaller due to the confinement effects provided by the steel tube. As the recycled coarse aggregate replacement percentage increases, the ultimate capacity and the stiffness of the RACFST members decrease and the creep and shrinkage effects become more considerable. Due to the tremendous deviation of the mechanical behaviour of the RAC, the conclusions obtained by researchers on the mechanical behaviour of RACFSTs are slightly different, yet this will not affect the application of such members in practical engineering. The RACFST members provide a possible solution to effectively recycle the construction and demolition waste.