Enhancing mechanical performance of rubberised concrete pavements with sodium hydroxide treatment

This research evaluates performance of rubberised concrete prepared with sodium hydroxide (NaOH) treated rubber. Numerous studies have investigated the method of treating rubber with NaOH. However, the level of improvement achieved by this method has not been consistent between different studies. Hence, it is worthwhile to study application of this treatment method. Ten series of concrete specimens with different water cement ratios and a variety of rubber content were prepared. The fresh and hardened mechanical tests were conducted on concrete samples. It was found that the duration of 24 h for treatment of crumb rubber was the most promised duration, which resulted in favourable fresh and hardened concrete characteristics. Compared to rubberised concrete prepared with untreated rubber, rubberised concrete prepared with the 24-h NaOH treated method had 25 and 5 % improvement in compressive and flexural strength, respectively. It is experimentally indicated that using this treatment method resulted in notable improvement for the compressive strength, and moderate enhancement in the flexural strength.