Potential use of sugarcane bagasse and bamboo leaf ashes for elaboration of green cementitious materials

The paper presents the study of pozzolanic activity and hydration of cement pastes containing sugarcane bagasse (SCBA) and bamboo leaves ashes (BLA). Pozzolanic activity of binary and ternary mixtures of ashes was investigated using electrical conductivity measurements. A kinetic-diffusive model was used to quantify the pozzolanic reaction between ashes and calcium hydroxide solution. The influence of ashes on hydration of cementitious pastes was also investigated using thermogravimetry analysis, X-Ray diffraction, isothermal calorimetry and mechanical tests. The results showed that ternary mixtures of SCBA and BLA have a higher pozzolanic activity than the binary mixture of SCBA. Binary and ternary mortars have higher compressive strengths than the control mortar without mineral additives. Moreover, the replacement of cement by 10 wt% of SCBA and BLA leads to a decrease of the calcium hydroxide content and the heat of hydration. The results also showed that the production of 1 ton of binder with agro-industrial ashes needs lower energy than conventional cement. According to the results of the study, the use agro-industrial ashes in binary and ternary blend cements can bring economic, technical and environmental benefits for the industrial sector including fiber cement industry, precast plants and concrete producers. (C) 2019 Elsevier Ltd. All rights reserved.