<p>This research evaluates the treatment of weak subgrade soils (A-4 and A-6 soils according to AASHTO classification), using cement and lime stabilisers to enhance pavement design efficiency. The research investigates the influence of varying the moisture contents and stabiliser percentages, namely 2% and 4% cement, both alone and mixed with 1.5% lime. The characteristics of resilient modulus and permanent deformation have been assessed using repeated load triaxial tests. The findings have shown that moisture content can adversely influence the performance and strength of subgrade soils by decreasing resilient modulus values besides increasing permanent deformation in subgrade soils. However, soil treatment by stabilisers has substantially enhanced the overall mechanical strength, as the resilient modulus increased by 180% for soil type A-4 and 310% for soil type A-6. Finally, the research demonstrates that the type and content of the required stabiliser depend highly on the composition of subgrade soils. A cement treatment is effective in soils with a higher content of sand and silt, while a compound treatment of cement and lime can provide significant mechanical strength for subgrade soils with a higher clay fraction.</p>