Sustainable Cements Containing Sugarcane Bagasse Ash and Limestone: Effects on Compressive Strength and Acid Attack of Mortar

Abstract

Sustainable cements are an important alternative to reduce the environmental impact of the cement industry by lowering the clinker-to-cement ratio with supplementary cementitious materials. In this respect, the present study aimed to evaluate the influence of partial clinker replacement by sugarcane bagasse ash (SCBA) and limestone filler (LF) on the mechanical and durability performance of mortars. Four blended Portland cements were produced with binary and ternary mixes of clinker, SCBA, and LF. An ordinary cement was also produced for comparison purposes. All five cements were characterized and applied in mortars in order to assess compressive strength and water absorption. Next, 28-day specimens were immersed in a sulfuric acid solution for 56 days to investigate deterioration using mass loss, length variation, water absorption, and compressive strength tests. In general, the combination of SCBA and LF produced more sustainable cements with suitable properties, as SCBA improved the mechanical behavior, while LF improved the durability performance of mortars. In this context, ternary mixes with 14% SCBA and 14% LF are indicated for mechanical uses, while 7% SCBA and 14% LF are recommended for durability purposes, as both maintained the respective properties of the reference cement.