Behaviour of Normal Concrete Us ing Superplasticizer under Different Curing Regimes
The performance of concrete primarily depends upon the type and ratio of its constituents, compaction, curing conditions and admixtures used during curing process. Part of this research emphasis to calculate the consequences on strength of concrete when water-cement ratio is constant and the increase in slump occurs with the increase in amount of superplasticizer by percentage. The rest of the investigation is carried out to study the effects of superplasticizer with different dosages under different curing regimes at an ambient field temperature ranges between 45°C-50°C. For this purpose, a concrete mix at 20MPa with all parameters constant was prepared by using an ASTM C494 type A, and F, anionic melamine polycondensate non-toxic superplasticizer with no chlorides. Different dosages of superplasticizer were used in different batches of all 95 specimens, and cured under different curing conditions and then tested for compressive and tensile strengths following ASTM standards. In all cases, th e water curing up to 28 days testing showed maximum strength. The highest and lowest values of compressive strength were obtained with the addition of 0.5% and 1% superplasticizer respectively. It was found that without increasing the W/C ratio, the addition of superplasticizer exhibits increase in strength.
Superplasticizing Additive Material on Concrete Performance and Effect on Concrete Performance in the Self-Locating Concrete Production: Literature Review
This survey presents a literature review on the superplasticizing additive material on concrete performance and effect on concrete performance in the self-locating concrete production with given a literature review and survey. That done through spotlight on the concrete and its properties, as well as, clarify the effect of chemical additives on fresh and hardened of the concrete. Explain the importance of superplasticizing additive material, and clarify the effect of adding material on concrete performance. The study concluded that substantial improvement in the concrete properties after use of the superplasticizer with high range water reducer, superplasticizer has given results that are more promising. Keywords : Concrete; Superplasticizing; performance; properties; and effect.
Effect of Conditioning Temperature on the Strength and Permeability of Normal- and High-Strength Concrete
In order to evaluate the effect of the conditioning temperature on strength and permeability properties of concrete a series of compressive, indirect tensile and permeability tests were performed on concretes (designed to have 28-day compressive strengths of 40 and 100 N/mm2) conditioned at temperatures of 85 and 105 °C. The results show that, for both the normal- (NSC) and the high-strength concrete (HSC), comparable 28-day test results were obtained from strength tests performed on concrete conditioned at 85 and 105 °C. The permeability results were also somewhat similar for the two conditioning temperatures, although greater differences than previously reported were observed. Conditioning at both 85 and 105 °C was identified as adequate, with the preferred temperature of conditioning being 105 °C.