COMPRESSIVE STRENTH OF RE-VIBRATED CONCRETE CONTAINING LOCUST BEAN EPICARP EXTRACT AND BIDA NATURAL STONES

Abstract

ABSTRACT The compressive strength of re-vibrated concrete containing locust bean epicarp extract and Bida natural stone (BNS) as be presented. One hundred and sixty-eight concrete cubes were produced in six batches, in which twenty-eight cubes was produced in each of these batches. However, two of these batches were at 0% LBEE + 100% OPC and 100% LBEE + 100%OPC, the rest are at cement reduction content of 5, 10, 15 and 20% respectively but all the other concrete mix ingredients remained constant. The epicarp used was at a constant concentration of 0.1kg/l. The concrete mix adopted was 1 :2 :4 using ordinary Portland cement with water-cement ratio of 0.5. The preliminary result shows that the aggregate fall within the BS requirement. Concrete cubes were cast with re-vibration time lag intervals of 10minutes for the period of a 60minute re-vibration process and cured for 7 and 28days. When tested for their respective compressive strengths, the result obtained shows that there is an increase in compressive strength of the concrete with an increase in re-vibration time lag. The result also shows that the introduction of LBEE increase the compressive strength of concrete produced despite cement reduction up to 20%. The maximum compressive strength for all batches at 28days curing is obtained at 60 minutes’ re-vibration time interval for the concrete. The maximum attained compressive strength for 28days curing is 38.65N/mm2 for C2 (100% LBEE + 100% OPC) is higher than 34.42N/mm2 for C1 (0% LBEE+ 100% OPC). This indicates that the uses of LBEE have increased compressive strength of concrete when re-vibrated.