Performance Assessment of Stabilised Fine Sand Incorporating Crushed Bricks for Sustainable Pavement Layers

This study examines the development of sustainable pavement layers using mechanically stabilised mixtures of crushed bricks (CB) and fine sand (FS). Experimental mixes were prepared at an FS–CB ratio of 1:1.6 with cement contents ranging from 2% to 12% by weight. Mechanical property was evaluated through unconfined compressive strength (UCS), California bearing ratio (CBR), modulus of rupture (MOR), indirect tensile strength (ITS), and indirect tensile stiffness modulus (ITSM) tests. Results indicate that cement addition significantly enhanced UCS, CBR, MOR, and ITS of the FS–CB mixtures. A UCS value of 2.2 MPa was achieved at 4% cement, with stable strength development up to 8% cement content. Durability, assessed through mass loss, remained below 10% for cement contents ≥4%, meeting standard requirements. Drying and autogenous shrinkage strains were limited to 0.0008 and 0.0007 mm, respectively. Microstructural analysis confirmed the formation of ettringite and calcium silicate hydrate, correlating with strength improvement. These findings demonstrate that cement-stabilised FS–CB mixes represent an environmentally sustainable alternative to conventional pavement materials.