Authors : Gideon Bamigboye, Adeola Adedeji, David Olukanni and Kayode Jolayemi
Abstract: The study investigated the reliability of gravel as partial replacement of granite in concrete production. Concrete was produced using various percentages of granite/gravel combination. Two different mix ratios of 1:2:4 and 1:3:6 were employed. Slump tests were carried out on fresh concrete, compressive and split tensile strength tests were performed on hardened concrete. Reliability analysis was carried out on available data to estimate the failure probability. The reliable percentage of gravel from compressive strength view point was 40% with a value of 21.15 N/mm2 for 1:2:4 and 30% with 15.17 N/mm2 for 1:3:6 mix ratios at 28 days. Satisfying minimum requirement of BS 8110:1997. There was a significant reduction in split tensile strength as gravel percentage increases beyond 40% for 1:3:6 mix ratio. Similar trends were observed for 1:2:4 mix ratio. Linear regression analysis was used to reliably predict characteristic strength based on any coarse aggregate combination with positive high values of coefficients of correlation (R2) of 0.983 and 0.937, respectively for compression and tension behavior. Comparing the result of the probability of failure obtained with the ISO 2394:1998 (E) standard it was found that g(⨱)>0 limit state was satisfied which indicated that the structure is safe.
Gideon Bamigboye, Adeola Adedeji, David Olukanni and Kayode Jolayemi, 2017. Reliability of Gravel in Place of Granite in Concrete Production. Journal of Engineering and Applied Sciences, 12: 5121-5128.