Flexural Properties of Concrete Beam using Rice Husk Ash (RHA) a Partial Replacement of Cement

Abstract

The research work examines the structural properties of concrete beam (flexural strength and deflection)under loading with partial replacement of cement with Rice Husk Ash (RHA).The Pozzolanic potential of RHA came to bear. Samples were made for various percentage of replacement (10%, 20%, 30% and 40%) with0% replacements for the control and tested at 7, 14 and 28 days. The results showed that there was an increase in flexural strength from 7 to 28 days with 6.0, 6.0, 3.6, 5.2 and 4.6 N/mm2 for the 28days test and 30% replacement, maintaining the same flexural strength for the entire test. It was also observed that there was a decrease in deflection value at rupture with progression in age with increase RHA content showing lesser capacity to carry imposed load. However, the water/cement ratio for the 30% AND 40% RHA/cement samples were increased to ensure a workable mix. These improved the result obtained when compared with the 20% RAH/cement having similar w/c the control and 10% RHA cement Samples. Setting time and slump test were also carried out and the results shows that with increase in RHA content in cement, lower values were obtained for the initial and setting time and for the slump test. It is recommended that 10% replacement can be used instead of the control and 20% and 30