Title: Sustainability Assessment of Ground Improvement Techniques: Comparative Analysis of Lime, Cement, Biopolymers and Geopolymers

Program: Civil Engineering MS

Committee Chair: Bhaskar C. S. Chittoori

Committee: Bhaskar C. S. Chittoori, Nick Hudyma, Moji Sadegh

Abstract: Ground improvement design (GID) is a vital part of constructing safe, long-
lasting infrastructure. Traditionally, this is done with a chemical additive such as lime or
cement that is mixed with in-situ soil to improve soil parameters such as compressibility,
and strength. These stabilizers produce high amounts of carbon emissions. As a response,
engineers and researchers are beginning to develop new stabilization methods using
biopolymers and geopolymers in hopes of achieving comparable soil stability results as
well as reduced environmental impacts.
This thesis work integrates a life-cycle analysis (LCA) and life-cycle-cost-
analysis (LCCA) framework to evaluate and compare four soil stabilizer types: lime,
cement, biopolymers, and geopolymers. The comparison tool assesses and compares both
the costs and embodied carbon emissions associated with manufacturing/processing,
material transportation, and initial construction. Numerical and visual results are
generated, allowing for all categories to be easily compared with one another across the
specified stabilizer. A case study has been conducted for a US-95 roadway section
located in Marsing, Idaho. The results of this case study reflect positively on the use of
polymers, particularly geopolymers, as a soil stabilizer. Geopolymers outperformed
traditional stabilizers both in carbon emissions and overall monetary cost, reducing
emissions by approximately 85% and cost by 64% relative to typical cement treatment
The developed comparison framework supports the implementation of sustainable
roadway infrastructure using data-driven material selection.