Expansion under water and drying shrinkage of rubberized concrete mixed with crumb rubber with different size

In this study, the expansion under water and the drying shrinkage of rubberized concrete used in pre-cast lightweight panels are investigated. Two sizes of crumb rubber are used: No. 6 (passing sieve No. 6) and No. 26 (passing sieve No. 26). Four experiments are carried out: absorption, compression, expansion and shrinkage. The size of the crumb rubber affected the properties of crumb rubber in different ways. Rubberized concretes with large sized crumb rubber (6CR) appear to have higher absorption than those with small sized crumb rubber (26CR). In the case of strength, both crumb rubbers clearly cause the compressive strength to decrease. The 6CR also exhibits higher expansion and lower shrinkage than the 26CR. The crumb rubber’s size and shape together with the non-polar effect are believed to play an important role on this phenomenon.