Effects of Using 0.5, 0.55 and 0.6 Water Cement Ratio Separately With a Nigerian Grade 42.5R Portland Cement

Abstract

This research paper is for the purpose of disseminating the results of an investigation into the effect of water cement ratio of 0.5, 0.55 and 0.6 separately while producing most commonly practiced concrete of cement, fine aggregate and coarse by 1:2:4 mixtures. This research study is limited to the use of newly grade 42.5R Portland cement that is being produced in Nigeria recently and of which is readily available. River sand was used as fine aggregate and coarse aggregates used separately were washed gravel, 19 mm and 12.5 mm granites. Nine different concrete mixtures were produced and it is important to note that the results of their slump tests deviated considerably from that of the compacting factor tests correspondingly while considering the degree of workability values. Conducting this research the potential impact derived is that only the use of 19 mm granite with water cement ratio of 0.5 and 0.55 achieved at 28 day flexural strength concrete grade of 4.92 N/mm2 and 4.84 N/mm2 respectively whilst are marginally greater than the standard specification value of 4.5 N/mm2. The significance of this study is that while at when the flexural strength of concrete is satisfied the corresponding tensile strengths values which are 2.684 N/mm2 and 2.590 N/mm2 do not satisfy the required standard specification values which are respectively 3.355 N/mm2 and 3.238 N/mm2. The contribution to knowledge as regards to this research work is in the enlightenment benefit revealed upon the possible prevention of economic loss that can occur due to early rigid pavement failure for roads, petroleum filling station concrete pavements in cities and rural towns or yards for offices and factories due to design of poor concrete proportioning and the use of the new cement.