Study of the Effect of Hemp Fibers and Brick Waste Powder on the Mechanical Characteristics of Mortar: Experimental and Statistical Analysis

This study aims to optimize the mechanical and rheological properties of cementitious mortar by incorporating hemp fibers (HF) and brick waste powder (BWP), with the goal of developing a more sustainable and eco-friendly construction material. Using response surface methodology (RSM), different proportions of HF (0, 0.25, 0.5%) and BWP (0, 10, 20%) were tested to optimize flowability, compressive and flexural strength. The experimental results indicate that the optimal composition, 0.25% HF and 10% BWP, significantly enhances mechanical performance while maintaining workability. Furthermore, the outcomes show that adding 10% BWP and around 0.5% HF considerably reduced the rheological characteristics, as seen by a longer flow time in comparison to other combinations. The ideal cement substitution rates, as determined by RSM, were 11.46% of BWP and 0.31% of HF. The study demonstrates the feasibility of using natural fibers and recycled materials in eco-friendly mortars, offering a sustainable alternative for construction. The predictive accuracy of the RSM model was validated through experimental verification, with results deviating by less than 5%. These findings contribute to the advancement of green building materials and sustainable construction practices.