Combined effects of rice husk ash and nylon fiber on engineering properties of cement mortar

Abstract

Utilization of waste materials is of utmost importance in creating a sustainable future. Industrial waste as well as recycled materials are used as supplementary cementitious materials in order to preserve the environment as well as to enhance the properties of the construction material. In the reporting work, rice husk ash (RHA) and nylon fibers were added to cement mortar (a mixture of cement, sand and water) to investigate their individual, as well as combined effect on flexural and compressive strengths, sorptivity, and abrasion resistance of cement mortar. Test results obtained in this study indicate that RHA can be blended up to 10% by weight of cement to obtain higher flexural and compressive strengths as the addition of RHA improves the strength of the cement paste by enhancing the production of calcium-silicate-hydrate. Nylon fiber reinforcement with 0.5 vol% showed efficient increment in flexural and compressive strengths of the mortar as a result of fibers holding the elements of the composite together. Replacement of cement with 10 wt% RHA effectively reduced the sorptivity of mortar as the addition of RHA results in the formation of a dense calcium-silicate-hydrate structure reducing the porosity and blocking the capillaries inside the paste. Addition of 0.5 vol% nylon fiber to the cement replaced with 10 wt% RHA showed an increase in abrasion resistance of the mortar as nylon fibers can retain during longer time period of stress due to their high elasticity. Overall results indicated that the combined addition of rice husk ash and nylon fibers can increase the performance of cement mortar effectively by increasing its mechanical as well as durability properties.