Construction of the pavement layers on soil subgrade with better properties reduced the thickness of the pavement and consequently has a remarkable effect on the cost of construction of the pavement. The construction of the pavement on expansive soil is tedious task and becomes challenging to the highway engineer. Over decades, the effort is being done to strengthen the soil subgrade with expansive properties. In the present study, recycled concrete aggregates were mixed with the expansive soil, and it was proposed to evaluate the strength of stabilized soil with recycled concrete aggregates. This experimental study evaluates the viability of using recycled concrete aggregates (RCA) for improving the engineering properties of clay soils. A comprehensive series of moisture density relationship, UCS, Atterberg limits, and CBR was performed on carefully proportioned mixtures of RCA and expansive soil. Clay soils mixed with RCA has shown the improvement in UCS up to 20% of RCA, and CBR has been increased to 7.5% with RCA content of 25%. Laboratory results showed that adding of RCA to expansive soil reduced Atterberg limits, Mixing RCA with clay soils results in stronger, stiffer subgrade of road pavements. Later the test results were analyzed with IIT pave software stress–strain results were obtained for modified soil, the numerical result indicates that the strength of stabilized soil with aggregates can be used for low volume roads. This study indicates that use of RCA in subgrade will be an efficient material in ground improvement techniques.