COMPARING DIFFERENT CEMENTS IN HIGH-PERFORMANCE CONCRETE

Eight cements encompassing different types, manufacturers, and plant locations were each examined in two classes of high-performance concrete (HPC) mixtures. Class I and Class 2 mixtures were designed to achieve compressive strengths of approximately 60 and 75 MPa (8700 and 10,880 psi) at 28 days, respectively. Criteria for comparing mixtures included workability, compressive strength, splitting tensile strength, and modulus of elasticity. Mixtures containing a Type III cement achieved the highest compressive strength at all ages tested, most significantly at early ages. At 28 days, cement characteristics influenced splitting tensile strength more significantly than compressive strength and compressive strength more significantly than modulus of elasticity. The ACI 209 equations underestimated the rate of compressive strength development at early ages. The ACI 363R equation was mostly accurate within ′ 10% in describing splitting tensile strength. The ACI 363R equation underestimated modulus of elasticity by more than 10%, while the ACI 318 equation, extended beyond its valid range, underestimated most of the modulus of elasticity results. The applicability of these empirical relationships must be confirmed for different cements used in HPC.