Potential utilization of sugarcane bagasse ash for developing alkali-activated materials

Sugarcane bagasse ash (SBA) is a by-product generated from cogenerations in sugar industries. This study is aimed at investigating on performance of alkali-activated binder using SBA and ground blast furnace slag (GBFS). The proposed mixtures were developed by changing GBFS/SBA ratios in blends (i.e. 100/0, 90/10, 80/20, 70/30, and 60/40) and silicate moduli (M-s = 0.6, 0.8, 1.2). Several results are highlighted: (1) alkali-activated GBFS/SBA pastes perform a quick hardening with an increase in M-s; (2) testing specimens cured in room-air ambient have the 28-day compressive strength beyond 110 MPa; and the 90/10 one shows the highest mechanical strength and manifested the best sulfate resistance and the lowest water absorption; (3) magnitude of drying shrinkage is smallest for 80/20 sample and following by the 90/10 sample. In summary, with balance of fresh behavior, strength, and shrinkage, a substitution up to 20% SBA could be appropriate to manufacture a sustainable binder.