Analysis of the influence of supplementary cementitious materials used in UHPC on modulus of elasticity

Abstract

The paper presents the results of static and dynamic modulus of elasticity measurements that were conducted on high-performance concretes with partial replacement of cement by supplementary cementitious materials (SCM). Metakaolin, microsilica and fly ash were used as SCM, the replacement levels were 10 %, 20 % and 30 % of cement weight. The tests were conducted on cylindrical samples 100 mm in diameter and 200 mm in height. Dynamic modulus was measured at the age of 1, 3, 7, 14, 21 and 28 days with the use of non-destructive ultrasound pulse method. Static modulus was determined by destructive compression test. The highest values were reached for fly ash at 20 % and 30 % replacements. Samples containing metakaolin had always lower modulus than the reference concrete. The coefficients for recalculation of dynamic modulus to static modulus were derived as 0.95 for reference concrete, 0.80 for metakaolin concrete, 0.85 for microsilica concrete and 0.90 for fly ash concrete.