Expansive soil is known for its ability to undergo significant volume changes in response to changes in moisture levels. Several investigations have been conducted to explore the stabilisation of expansive soils, encompassing a variety of reinforcement techniques and stabilisation approaches. Analysing dynamic properties such as shear modulus and damping ratio in expansive soil is imperative as they provide vital insights into the soil's response to dynamic loads. The use of lime and fibre treatment for stabilising expansive soil offers a comprehensive solution that addresses both chemical and physical stabilisation. This approach enhances soil properties and reduces the risk of damage to structures. To understand the complex behaviour of soil systems under varying conditions, cyclic triaxial tests on expansive soil were conducted using fibre-lime treatment. The variations in dynamic shear modulus and damping ratio with respect to shear strain amplitude, as well as the dynamic shear stress-strain curves, were studied across various confining pressures. The paper also presents the small strain shear modulus and modulus reduction curves. Besides, for a comprehensive understanding of the microstructural reactions of the fibre-lime-treated soil, specimens subjected to cyclic loading were examined using SEM analysis. A comparative analysis, examining the dynamic properties of soil under varying lime percentages, with and without 0.5% polypropylene (PP) fibre, as well as comparing scenarios with different lime contents between 0 and 0.5% PP fibre conditions has been presented. The experimental findings suggests that the fibre-lime treatment led to an enhancement in the dynamic shear modulus and damping ratio, with the increase of confining pressure. From the SEM analysis of the fibre-lime-treated soil, the microstructure displays a fabric-like pattern with cementitious gel connecting soil particle clusters. The images also show clay particles bonding together, forming a compact structure.