Viability of Napier Grass Ash as Partial Substitute of Cement in CHB

Abstract The effects on the physical and mechanical properties of Napier grass ash (NGA) as substitute for ordinary Portland cement (OPC) concrete hollow block (CHB) were investigated. Mix ratio 1:2:4 with water-cement 0.60, 10%, 15%, 20% NGA replacements adapted. Experimental procedures testing conformed to American Society Testing Materials (ASTM) standards. Slump values, in comparison control, showed a decline 16.67%, 25%, 58.33% replacements, respectively, which correlates water absorption result. denser CHB, lower moisture content. Compressive strength results revealed that all substitutes performed better than control sample. NGA-20% had highest compressive 4.2 MPa (individual unit) 3.9 (average 3 units) after 28 days curing. Overall, replacement was not viable load-bearing but ideal nonload-bearing CHB using mix design.