Experimental Study on Sound Absorption and Insulation Characteristics of Hemp-Perlite Fibre-Reinforced Concrete

Statement of Problem. The increasing demand for sustainable and energy-efficient materials has prompted the evaluation of lightweight fibre-reinforced concrete, which exhibits notable acoustic and mechanical performance. The work aims to study the mechanical and acoustic properties of hemp fibre integrated as a natural reinforcement and perlite granules as a lightweight aggregate. Five mixed proportions are developed with a conventional mix and others with 7 % perlite replacement and hemp fibre addition of (0.5, 1.0, and 1.5 % by volume). Mechanical behaviour, density and water absorption are evaluated to evaluate the effect of material modification. An impedance test is conducted to determine the sound absorption coefficient at frequencies of 250, 500, 1000, and 2000 Hz. Result. Results showed that compressive strength decreased with increasing fibre and perlite content, attributed to increased porosity and disrupted matrix compaction. The density decreased gradually with the material of altered proportions, and the reason was to use lightweight concrete. Sound absorption was increased reaching a peak of 0.35 at 1000Hz with a 1.5 % addition of hemp. Conclusion. The study introduces the efficacy of the mixture of hemp fibres and perlite granules and powder together to improve the acoustic performance and strength to be applicable in non-structural sound-sensitive conditions. The results are used in the creation of environmentally-friendly, acoustic materials that are lightweight and designed to meet the contemporary construction demands.