Quality assessment of sandcrete blocks produced along-Oke Fomo Area, Ilorin, Kwara State

Abstract

In this study, the quality of sandcrete blocks produced along Oke-fomo, a rapidly developing area of Ilorin, Kwara State, Nigeria was investigated. Seven commercial block industries were randomly selected from where five sandcrete block samples of 450 x 225 x 225mm were sourced. Fine aggregate samples were also obtained from each of these industries and transported to the materials laboratory of Ministry of works, Ilorin. The tests carried out include sieve analysis and compressive strength. The dimension of the blocks was also checked. The mix ratio, curing techniques/duration and batching method were obtained through interaction with the block manufacturers. The results obtained showed that the aggregates are suitable for block making having satisfied the overall grading requirement specified in BS EN 12620 (2002). The mix ratio adopted by the industries ranges from 1:12 to 1:14 which is against the standard 1:6 specified in NIS 87:2004. The compressive strength of the sandcrete blocks was found to be below the Nigerian Industrial Standard (NIS) 87:2004 specification with an overall highest compressive strength of 0.98N/mm² when compared with the NIS 2.5 and 3.5N/mm² for non-load and load bearing walls respectively. The study concluded that block producer should adhere strictly to the laid down standard especially in mix ratio and curing duration. However, it was recommended that formal training should be periodically organized for block industries and the public should also be sensitized about the danger in using substandard sandcrete blocks. This will to a large extent improve the production of quality sandcrete blocks and promote the market for the standardized ones while averting consequences associated with weak sandcrete blocks such as collapse of walls.