Effect of the mix composition with superplasticizer admixture on mechanical properties of high–strength concrete based on reactive powders

Abstract

This paper outlines effect of the mix composition on mechanical properties of high-strength concrete based on aggregate size like in of Reactive Powder Concrete (RPC) but without fiber reinforcement. The main purpose which guided the authors choosing proportion of water and superplasticizer (SP) was to achieve a similar consistency in the test slump for various concrete mix. Test results for 3 groups of superplasticizers, designated as D -with chemical base -acrylic polymer, V -with chemical base -polycarboxylate ether, P -with chemical base -modified polycarboxylates, two cement groups, designated as Cem A -with fineness Blaine 3980 cm 2 /g, Cem B -with fineness Blaine 4430 cm 2 /g and 2 types of aggregate: basalt and granite were presented. After curing for 1, 7 and 28 days samples were tested for compressive strength and flexural tensile strength. The article also presents the study of the elemental composition and structure of the SP with the use of the SEM electron microscope. The amount of solid particles in the SP was also determined by the water vaporization. The assumption of the paper was to maintain the consistency of the mixture at the S2 level according to the Eurocode standard. The paper proposes a method based on SEM analysis in order to select a superplasticizer with the best ductility parameters, and the best results of the compressive and flexural tensile strength of concrete samples were obtained. The best results for compressive strength after 28 days are obtained for concrete series with the polycarboxylate ether superplasticizer and modified polycarboxylate ether superplasticizer in combination with the use of type A cement and it is greater than for the concrete series with type B cement by 11.7%.

Experimental Calibration of a Homogeneous Substitute Material Model for Reinforced High-Performance Concrete Modeling

“…The flexural tensile strength of concrete was determined on the basis of Formula (6) and Table 1 . The data in Table 1 were determined on the basis of [ 16 , 25 , 26 , 27 , 28 ]: where…”

Comparative analysis of natural nanosilica versus commercial nanosilica on compressive strength and durability of high-performance concrete

“…This research is to carry out a comparative analysis using natural nanosilica compared to commercial nanosilica (NSc), when used alone and when combined with silica fume in high performance concrete, on the compressive strength and durability of concrete. In the concrete mixture, a polycarboxylic ether type superplasticizer is used which can increase the compressive strength [22].…”