| The main objective of this study was to investigate the freeze-thaw durability of rubberized portland cement concrete through the addition of two types of crumb rubber particles, ambient and cryogenic. The results of rubberized concrete were compared with both non-air-entrained concrete and air-entrained concrete without the addition of rubber. The effect of the alkalinity of cement, the absence of super-plasticizer, the vibration time and frequency of the consolidation of fresh concrete, and the addition of supplementary cementing materials with high loss-on-ignition (LOI) that affects the air content in concrete, such as rice husk ash, was studied. Also, comparative studies were conducted with latex emulsions to understand if crumb rubber has any similarity with latex on concrete properties.;The investigations on freeze-thaw durability of crumb rubber concrete concluded that the use of finer sized particles i.e. ;However, the rubber concrete specimens prepared from combinations of RHA with ;In summary, the findings from this research indicate that the use of finer rubber sizes and higher rubber replacement levels, improves the freeze-thaw durability performance of concrete, even though the strength of the concrete is decreased. However, a difference in the properties of rubberized concrete with ;The hydrophobic nature of the crumb rubber and increased specific surface area (SSA) of finer size fractions of crumb rubber particles appears to be the principal mechanism leading to the increased air entrainment in the rubberized concrete. Standard petrographic examination methods are adequate to characterize the air content parameters even in rubberized concretes. If the finer crumb rubber particles can be used as a partial replacement to fine aggregates, it can reduce the usage of natural mineral aggregates greatly and minimize their rapid depletion. Crumb rubber particles may prove to be a sustainable option for producing frost resistant concrete and also provide an opportunity for economic and environmental friendly solution for the disposal of high amount of waste tires in the landfills. (Abstract shortened by UMI.). |
