Sustainability Analysis of MICP-Treated High-Fines Soil with Geocell Reinforcement for Pavement Base Stability

This study explores sustainable pavement base strategies combining microbial-induced calcite precipitation (MICP) and geocell reinforcement as alternatives to traditional methods reliant on virgin aggregate extraction. Conducted on a section of US Highway 95 in Idaho, the trial treated high-fines soil with MICP and reinforced it with geocells, comparing performance against conventional aggregate base. Life cycle cost analysis and embodied carbon quantification over 40 years showed the MICP–geocell section achieved about 35% lower greenhouse gas emissions and 12% lower costs at a 5% discount rate. Benefits mainly stem from reduced aggregate use and maintenance, though emissions from urea and calcium chloride production partly offset these gains. Limitations include short-term monitoring, omission of end-of-life impacts, and eutrophication risks from ammonium byproducts. Overall, MICP with geocell reinforcement appears promising for sustainable pavement construction, but requires longer-term study and comprehensive environmental assessment.