Abstract:
At present, there are a lot of technological development researches on concrete materials. Those provide researchers and engineers have greater knowledge and understanding. They have created strength enhancing mineral admixture that helps improve the reaction in portland cement mixture. This synthetic mixture helps hydration reaction. Its chemical composition is similar to that of portland cement. Researchers have tried out to replace strength enhancing mineral admixture in concrete and it was found that its reaction in early strength development went well. It was expected that the replacement of strength enhancing mineral admixture will help change both basic properties and durability concrete.
This research aimed to study the basic properties of concrete containing strength enhancing mineral admixture (SA) by adding and replacing it in portland cement type 1 (OPC1), portland cement type 1 mixed with limestone powder (OPC1+LP) at 5.5, 6.5 and 7.5% by weight, and 3.5, 4.5 and 5.5% by weight in portland cement type 3 (OPC3).
It was found that the autoclave expansion of paste containing SA was less than that of OPC1, OPC3 and OPC1+LP paste. The autoclave expansion of paste containing SA with partial replacement was lower than that of paste containing SA addition. Moreover, the more mixture of SA, the more autoclave expansion occurred whereas the expansion in calcium hydroxide solution of mortar containing SA was higher than OPC1, OPC3 and OPC1+LP mortar. The expansion in calcium hydroxide solution of mortar containing SA with partial replacement was lower than that of mortar containing SA addition. In addition, the more addition of SA, the more expansion in calcium hydroxide solution occurred. Besides, slump and slump loss of concrete containing SA was lower than those of OPC1, OPC3 and OPC1+LP concrete whereas setting time of concrete containing SA was higher. However, using different quantity of SA gave the same results of slump, slump loss and setting time of concrete. Furthermore, compressive and tensile strength of concrete containing SA was higher than those of OPC1, OPC3 and OPC1+LP concrete. Adding or replacing different quantity of SA yielded the same results. Finally, autogenous shrinkage of concrete containing SA was more than that of OPC1 concrete. The autogenous shrinkage of SA replacement concrete was lower than that of SA addition concrete. In addition, adding more quantity of SA caused the same autogenous shrinkage.