Experimental investigation on aggregate interlocking concrete prepared with scattering–filling coarse aggregate process

To secure good flowability and segregation resistance of the fresh concrete mixture, the volume fraction of the coarse aggregate in the conventional plastic concrete is controlled at a relatively low level. A new type of coarse aggregate interlocking concrete was prepared with a new invented concrete placing method named as scattering–filling aggregate process. The strength of concrete prepared with this method obviously increases whereas the shrinkage ratios of them decrease significantly with the extra adding aggregate volume ratio from 10% to 30%. These concretes with high strength and low shrinkage can be prepared with much lower cement dosage compared to the conventional process. The SEM observation indicated that the interfacial transition zones at the interface of the added aggregate are much tighter than those of the original aggregate. The interlocking and homogeneous distribution of the coarse aggregate and the water absorption of the extra added coarse aggregate contribute to the strength improvement and performance modification.