Evaluation of life cycle assessment (LCA) use in geotechnical engineering

In recent years, there has been a growing emphasis to incorporate sustainability metrics into geotechnical engineering design decisions, driven by the surging eco-consciousness of industry standards. Consequently, life cycle assessment (LCA) has emerged as a popular method for evaluating the environmental impacts of geotechnical systems or projects. This paper conducts a critical review of 54 publications that apply LCA to various geotechnical systems, including deep foundations, biogeotechnics, dams, ground improvement, earth retaining structures, tunnels, and others. This review assesses the current state of practice for LCA in geotechnical engineering, identifies common barriers to implementation, and provides suggestions for successful execution. While sustainability practices have been more readily adopted by some subdisciplines of civil engineering including structural and transportation, geotechnical engineering faces distinct challenges due to its inherent site-specific nature, characterized by non-homogeneous soils and the necessity for bespoke solutions. Despite the notable increase in geotechnical LCAs, the absence of uniform standards remains a critical issue. Many studies could be improved by enhancing transparency in reporting data and results, clearly justifying input assumptions, and assessing the effects of variable soil conditions. Geotechnical LCA studies often concentrate on highly specialized problems, limiting the relevance of findings to other projects and impeding the development of clear recommendations for industry practitioners. Future research endeavors would benefit from establishment of comprehensive frameworks and multi-indicator models tailored to geotechnical systems to more accurately capture expected environmental impacts and opportunities for their reduction. A standardized approach could reduce redundancy in studies, encourage knowledge transfer, and provide a basis for broader applicability of sustainability practices in the geotechnical engineering profession.