Use of Aluminum Residue and Recycled Asphalt Pavement Materials to Stabilize Silty Clay Soil

Abstract

The effectiveness of mixing aluminum residue and recycled asphalt pavement materials (RAPs) with silty clay soil on the soil’s physical properties was discussed. The mixing material that is used enhances the silty clay soil’s volume changes and bearing capacity and reduces settlement. Different percentages of aluminum and asphalts by weight, ranging from 2 to 10% in increments of 2%, were used to determine the enhancement in soil properties gained using these materials. Physical and mechanical testing was carried out according to applicable ASTM and AASHTO testing methods. Soil mixtures of various ratios were studied in the laboratory to note the enhancements in the swelling behavior, shear strength parameters, Atterberg’s limits, optimum moisture content, and corresponding maximum dry density. Moreover, this investigation also included evaluation of the bearing capacity of subgrade material. The results of this investigation showed that the addition of aluminum residue and recycled asphalt materials to a silty clay soil with proper compaction would lead to an increase in the bearing capacity and dry density. In addition, an increase in the unconfined shear strength and a decrease in swelling and the shrinkage potential of the silty clay soil were also observed.