From the mix proportions of the concrete mixtures, it is noticed that fly ash mixtures need high dose of the air entraining agent to achieve the designed values while silica fume mixtures need low dose of the air entraining agent. Concerning the super plasticizer, silica fume mixtures need higher dose than those of fly ash ones. The mixtures that include ternary systems of fly ash and silica fume show that both silica fume and fly ash compensate each other regarding the dose of air entraining agent and super plasticizer.
3.2. Properties of hardened concrete
The compressive strength values of concrete were measured up to age of 180 days while tensile strength, static Young's modulus, and dynamic elastic modulus measured at age of 28 days. The measured properties of hardened concrete are summarized in Table 3.