STUDY OF FRESH PROPERTIES OF UHPC USING VOLUME PASTE APPROACH

Santhosh K, Savithri Karanth, Manoj V

Abstract: The packing density approach is used to calculate the UHPC mix required for the study. The Particle Packing Approach is adopted to minimize the volume of cement paste by minimizing the volume of voids in concrete. The present experimental study is on the rheological behaviour of four design mixes UHPC in which two mixes are with coarse aggregates of 12.5mm downsize and other two mixes are without coarse aggregates. The behaviour in fresh state of each mix is studied by varying the paste content. The two mineral admixtures used in all the mixes are 10% micro silica and 5% metakaolin replacing cement by weight. Manufactured Sand (M-Sand) and quartz sand are used as fine aggregates. Quartz sands consist of particle size ranging from 150micron to 45micron. 1% to 2% Steel fibres are used in all the mixes to resist shrinkage cracks in concrete mix. Paste content for each water binder ratio (0.3, 0.26, 0.22) is calculated using particle packing mix approach The fresh properties of UHPC Slump test, J ring, L-box test, V-funnel test and U-box tests are conducted as per EFNARC 2005 for different paste content. Corresponding 3 day and 28 day of compressive strength for the each paste content is determined and achieve compressive strength of 119.5MPa for mix without coarse aggregate and 105.36 mix with coarse aggregate.

Keywords: Packing Density, Paste Content, Rheological Behaviour, Compressive Strength.

DOI: https://doi.org/10.15623/ijret.2016.0510024