Strategies on Reuse of Clayey Expansive Soils as Embankment Material in Urban Development Areas: A Case Study in New Urbanized Zones

Volume changes in clayey expansive soils may result in the settlement or heave of structures, making such materials inappropriate in the design of soil structures. Lime and its derivatives provide an increase in the plastic limit of clay, and have gained considerable attention in soil stabilization techniques. In this regard, optimum lime addition combined with an innovative construction procedure provides new possibilities for the construction of roads in urban areas. In this study, the first straightforward strategy for the ionic immobilization of lime between clay laminar structures, based on a component self-assembly process, is presented. The method is applied to an area with expansive clays in the city of Madrid (Spain). The clayey soils were characterized by DRX, SEM, particle size distribution, swelling tests, and bearing capacity analyses. This strategy reduces the need for the transportation of discarded materials to landfill and the acquisition of new resources. In addition, the proposed methodology allows for a reduction in the environmental impact associated with urban development in expanding urban areas.