Coal bottom ash as partial replacement of fine aggregates in hollow load-bearing concrete masonry units

The cost of basic construction materials such as cement, ordinary sand and gravel have steadily risen over the years and the production and sources of all these materials may not constitute a lifetime, therefore, industrialized countries have studied and introduced industrial waste as an alternative material for construction. By tapping this undesirable and unused industrial waste we can also solve one of the country's major problems related to environment and proper solid waste disposal. Coal bottom ash considered to be one of the industrial wastes, coming from coal-fired thermal power plants in the country was used as fine aggregates, an alternative material for ordinary sand in the manufacturing of hollow load-bearing concrete masonry units. This study shows comparative results in terms of performance through comprehensive strength test of concrete masonry units with sand as fine aggregates and concrete masonry units with coal bottom ash as partial replacement for sand. The study has developed the optimum mixed design of hollow load-bearing concrete masonry unit with coal bottom ash as partial replacement for sand in terms of the cement-aggregate ratio, water-cement ratio and the coal bottom ash-sand proportion. This developed mixed design which utilizes this industrial waste aims in solving the disposal problem, provide means of livelihood projects for the people in the area affected and helps in the preservation of our natural resources in the provinces affected by this industrial waste.