Effect of Mixture Proportioning of the High Performance Cementitious – Limestone Composites on the Compressive Strength

Abstract

The focus of this work is on comparison the compression strength of the cementitious - limestone composite samples made according to different recipes. The study includes the results of own experimental research of the high performance cementitious - limestone composites as well as an analytical calculations of the mixture proportioning and designed compressive strength. Mixture proportioning based on the formulas of Funk and Dinger was determined. In the following step compressive strength based on the modified formulas Larrard was designed. Three test samples with dimensions of 100 x 100 x 100 mm were made for each recipe B1, B2, and B3. Information on the curing of research samples, cement, microsilica, limestone powder and limestone sand was presented. On the basis of experimental results after 7 days curing with using the proper amount of superplasticizer, the following section of the paper presents results after 28 days. Then a reference sample for the comparative analysis of the mixture proportioning was made and marked as B4. Based on the reference sample, the next samples with removed fractions (B5 < 0,063mm; B6 < 0,063mm and 0,063-0,125mm) were made. The last sample marked B7 with a different amount of cement in relation to samples B6 was also made. Results of compressive strength for samples B1-B7 were compared. Direct measurements allowed us to observe that B1 - B3 samples with different amounts of superplasticizer have compressive strengths differing by up to 3% both after 7 and 28 days. Samples marked B5 and B6 shown increased compressive strength by 6% and 12%, respectively in relation to the sample B4. The sample B7. The results demonstrated that sample B7 indicate the reduced compressive strength in comparison to sample B6.