Authors : M.A. Abdel-Aziz, M.A. Arab and R.M. Hussien
Abstract: Concrete retempering is the procedure that is used to restore the lost workability in ready mixed concrete. Adding an extra amount of water for retempering concrete is the common practice but adding an extra amount of water without exact calculation in mixture proportions makes compressive strength affects harmfully. As a result of delivery delaying or concreting in conditions of hot weather, abnormal slumps loss is expected, therefore, it is usual to modify the normal concrete placing and finishing procedures consequently. This research aims to evaluate different concrete retempering methods and their effect on concrete characteristics which gives the user the ability to choose the suitable method according to the expected concrete properties. In this research the experimental program was carried out to investigate the influence and the effect of retempering time (with 15 min time interval ranging between 0 up to 120 min) without any additions, retempering with adding water, superplasticizer and extra amount of cement paste on slump test and the mechanical properties of Normal Strength Concrete (NSC) and High Strength Concrete (HSC).
M.A. Abdel-Aziz, M.A. Arab and R.M. Hussien, 2019. Effect of Concrete Retempering Methods on Fresh and Hardened Concrete Properties for Normal and High Strength Concrete. Journal of Engineering and Applied Sciences, 14: 8903-8911.