Eco-Smart Geomaterials and Nano-Engineered Soils: Innovations in Geotechnical Engineering for Pollution Mitigation and Environmental Sustainability

Nanotechnology and smart materials have emerged as crucial fields for building, analyzing, and studying soil-related infrastructure systems with enhanced performance and sustainability. This review covers the recent progress in nano-engineered soils and smart materials, including their types and mechanisms of interaction with soil matrices, and further explains their prospective applications in stabilization, reinforcement, sensing, and ground improvement technologies. Widely used nanomaterials, such as nano-silica, nano clay, carbon nanotubes, graphene, and nano-calcium carbonate, have great potential to enhance geotechnical properties, including shear strength, compressibility, and permeability. A novel approach using smart materials, including piezoelectric materials, shape memory alloys (SMAs), electroactive polymers, and self-healing composites, bestows adaptive functions and integrated sensing capabilities upon soil systems, enabling real-time monitoring and adaptive behavior. This review also discusses the environmental consequences and sustainability considerations of implementing these advanced materials. In this regard, aspects of life cycle assessment (LCA), potential toxicity, and bioaccumulation risks are also highlighted, and the potential of eco-friendly and bio-inspired alternatives is highlighted as part of promoting green geotechnical practices and models of the circular economy. With advances on the horizon, the public implementation of these materials is impeded by challenges, including challenges with their dispersion, their long-term performance, their high costs, the lack of verifiable guidelines, and regulatory frameworks. Finally, the paper concludes with directions for future research, such as the necessity for field-scale validations, integration with Artificial Intelligence and Internet of Things technologies for smart soil systems, and formulation of eco-friendly, bio-compatible nanomaterials. This review emphasizes that nano-engineered soils and smart materials can reshape geotechnical engineering and offers forward-looking perspectives on how asset (infrastructure) owners and the construction industry may benefit from resilient, intelligent, and sustainable solutions.