Building with waste: performance of concrete incorporating organic fibres as cement additives

Agricultural waste is rising rapidly, and turning organic residues into construction materials offers a sustainable way to reduce environmental impact. This study examines concrete mixtures enhanced with mechanically treated date palm mesh (PM) and sugarcane bagasse (SCB) fibres. Sixty samples were prepared with fibre contents of 0%, 0.4%, 0.6%, and 0.8% by mass, were tested for slump, unit weight, absorption, compressive, flexural and tensile strength, and thermal conductivity. Increasing fibre content reduced workability, with slump values dropping from 175 mm in the control mix to 10 mm in PM 6. Unit weight remained between 2.2 and 2.44 g/cm3, while palm mesh helped reduce the water absorption to 5.8 kg/m³. The PM 8 mix achieved the highest compressive strength of 33.69 MPa, outperforming the 22.93 MPa control. Flexural and tensile strengths peaked at 6.6 and 3.22 MPa in the PM 6 mix. Thermal conductivity also improved, decreasing from 6.4°C in the control to 5.0°C in PM 6, indicating better insulation. Overall, adding 0.6–0.8% palm mesh fibres significantly enhanced concrete strength, durability, and thermal performance, positioning these fibres as an effective sustainable option for construction in hot climates.