This study investigated the extent to which the mechanical strength of commercially produced sandcrete blocks in Delta State, Nigeria, conforms to recognized international standards. Fifty sandcrete blocks (28 curing days) were sampled from ten known sandcrete block manufacturers in Warri municipal area, five blocks from each manufacturer. The compressive strength of the blocks was determined in accordance with the American Society for Testing and Materials (ASTM) International guidelines. The results showed that the compressive strength of all the blocks failed to meet the Nigeria Industrial Standard (NIS) benchmark for load loading sandcrete block, while only 20% of the blocks attained NIS requirement for non-load bearing walls. Field observation revealed that poor mixing ratio of the sandcrete; inconsistencies in the batching method and sand used in the production of the sandcrete blocks were responsible for the poor quality (low compressive strength) of the sandcrete blocks manufactured in the region. The findings of this study underscore the importance for the Nigerian Institution of Structural Engineers, to rigorously monitor the strength of sandcrete blocks made in Nigeria to ensure that their quality meets internationally recognized standards. This will reduce the occurrence of structural damage in Nigeria, due to the use of low quality blocks for wall constriction.
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