Effects of Sugarcane Bagasse Fiber Additives on the Mechanical Properties of Lime-Based Composites and their Compatibility with Traditional Lime-Based Mortars

Abstract

This study explored the incorporation of sugarcane bagasse fibers into lime mortars to potentially enhance the mechanical properties and durability of materials used in heritage structures made of unreinforced masonry. Assessment of the mixes and their compatibility with the traditional lime mortar mix used in conservation projects in the Philippines was also performed. Five (5) mortar specimen types containing different fiber content were prepared, each with twelve (12) samples. Flexural strength, compressive strength, ductility, and modulus of elasticity comprise the mechanical properties investigated while visual properties, chemical and mineralogical composition, pore space, mechanical properties, and hydrophilic behavior comprise the criteria for computing incompatibility degrees (IDs). Being the mix traditionally used in local conservation works, Mortar L0 (plain mortar) served as the control. Results showed that Mortars L4.6 (4.6% fiber content), L7.6 (7.6% fiber content), and L10.7 (10.7% fiber content) generally had lower mechanical properties compared to Mortar L0, except for the 14% increase observed in the compressive strength of Mortar L4.6. Mortar L1.5 (1.5% fiber content) had the best results having significant improvement in overall mechanical strength. It exhibited 6.8% increase in flexural strength, 38% increase in compressive strength, and 69.4% increase in modulus of elasticity values. Mortars L1.5, L4.6, L7.6, and L10.7 were computed to have IDs equal to 3.6, 1.1, 1.8, and 3.3, respectively. These indicate low to medium low incompatibility with Mortar L0. These findings highlight the viability of sugarcane bagasse fibers as reinforcement for lime mortars while maintaining sufficient compatibility with traditional lime mixes.