Influence of Selected Factors on HPC Strength Properties

Abstract

The paper presents the results of research, the objective of which was an evaluation of the influence of selected factors related to content on the resistance properties of high performance concrete. These factors were the water/binder ratio (W/S), the sand/binder ratio (P/S) and the PVA fibre content (V_f). An 18-point experiment plan was used. The mortars were made of the following ingredients: CEM I 52, 5R cement, silica fume, silica sand, PVA fibres, policarboxylate superplasticiser. The testing programme covered: tests of compressive strength per standard PN-EN 1015-11:2001 and tests of flexural strength per standard PN-EN 14651+A1:2007. Such an ingredient ratio was sought that will permit the achievement of the most advantageous strength properties (flexural strength and compressive strength). The conducted research shows that among the analysed factors, the greatest influence on flexural strength is exhibited by the content of PVA fibres. The highest values of flexural strength were achieved for a fibre content of Vf=3-3.7%. The addition of PVA fibres has lesser influence on compressive strength than the W/S ratio. The increase of the fibre content causes worsening of the workability of the concrete mix.