Bamboo ash as a sustainable supplementary cementitious material in concrete

Reducing carbon dioxide emissions from cement production is increasingly important in the construction industry. In the current research, the viability of using bamboo ash (BA) as a supplementary cementitious material for M25 concrete was assessed. The replacement ratio was varied (0%, 5%, 10%, and 15%). It was noted that greater BA fineness reduced workability as its percentage in the concrete mixture increased. The concrete compressive strength improved by 28.75% when 10% BA replaced cement, compared with the control samples at 28 days. However, further increases in the replacement of BA above 10% led to a reduction in the compressive strength. An increase in split tensile strength was observed at a 10% replacement rate. It has been established that water permeability decreased, reaching 10 mm for the 10% BA batch and 12 mm for the control batch. In addition, the rapid chloride permeability test of the concrete improved at moderate BA percentages. Structural tests on reinforced concrete beams indicated improved load and flexural characteristics in specimens with a 10% BA replacement rate compared to the control specimens.