Influence of Sugarcane Bagasse Ash on the Workability and Mechanical Behaviour of 3D-Printed Mortar (2026-03)¶

3D-printed mortar (3DPM) is associated with significant cement consumption, which raises substantial environmental concerns. This study investigates the reuse of sugarcane bagasse ash (SBA), which has a high SiO2 content, in 3DPM to reduce carbon emissions and to promote sustainable development. The raw SBA was first dried and then ground. Then, five mixtures with varying SBA dosages, ranging from 0 to 20% cement replacement, were developed and tested. This study examines the effects of SBA on key properties of 3DPM, such as flowability, hydration kinetics, setting time, and compressive strength. The results indicate that increasing SBA content reduces the flowability of the mixtures. It significantly reduces the setting time from 207.5 min of the control mix to 49.5 min as the replacement ratio is 20% due to finer particles. The isothermal calorimeter test results indicate that SBA accelerates the cement hydration process, potentially reducing the usage of an accelerator in 3DPM. Including SBA in the mortar mix significantly increased compressive strength within the first 24 h and also up to 28 days. This accelerated reaction boosts the early-age strength development of the concrete mixture, making it especially suitable for applications that demand rapid strength gain.