Crumb rubber used in concrete to provide freeze-thaw protection (optimal particle size)

The range of tests used was conclusive in that the <0.5 the crumb rubber particle size, provided the greater degree of air entrainment. The freeze-thaw cycle results suggested that crumb rubber provided freeze-thaw protection, as the plain concrete deteriorated compared to the concrete with crumb rubber additions. There was no definitive correlation between the compressive strength and the crumb rubber particles size, although the rubberised concrete had an average strength loss of 5.24% after 28 days. This research indicates that crumb rubber graded up to <0.5 mm is the optimum size to use, when crumb rubber granules are used to provide freeze-thaw protection in concrete.