Effect of Porosity/Binder Index on Strength, Stiffness and Microstructure of Cemented Clay: The Impact of Sustainable Development Geomaterials.

Searching for alternative material options to reduce the extraction of natural resources is essential for promoting a more sustainable world. This is especially relevant in construction and infrastructure projects, where significant volumes of materials are used. This paper aims to introduce three alternative materials, crushed ground glass (GG), recycled gypsum (GY) and crushed lime waste (CLW), byproducts of construction industry geomaterials, to enhance the mechanical properties of clay soil in Cartagena de Indias, Colombia. These materials show promise as cementitious and frictional agents, combined with soil and cement. Rigorous testing, including tests on unconfined compressive strength ( q u ) and initial stiffness ( G o ) and with a scanning electron microscope (SEM), reveals a correlation between strength, stiffness and the novel porosity/binder index ( η /C iv ) and provides mixed design equations for the novel geomaterials. Micro-level analyses show the formation of hydrated calcium silicates and complex interactions among the waste materials, cement and clay. These new geomaterials offer an eco-friendly alternative to traditional cementation, contributing to geotechnical solutions in vulnerable tropical regions.