Numerical-Based Feasibility Study of Road Culvert Deicing Using Geothermal Energy in Montana

Abstract

This study presents a numerical evaluation of a geothermal culvert deicing system to mitigate ice buildup and thermal degradation of frost-susceptible soils in cold regions such as Montana. A three-dimensional numerical model was developed in COMSOL Multiphysics (version 5.6) to simulate the coupled heat-transfer processes between embedded geothermal tubing, culvert structure, and surrounding soil. The model was validated using published experimental and field data from prior geothermal heating studies. Simulations were performed using inlet fluid temperatures of 10°C and 50°C, representing typical and high geothermal potential in Montana. The model was used to assess system performance across various design parameters and environmental scenarios, including water and ice inside the culvert. Results show that with adequate inlet temperatures and operational duration, the system can raise both culvert and adjacent soil temperatures above freezing, reducing the risk of ice blockage, frost heave, and repeated freeze–thaw cycles that degrade soil strength and compromise long-term embankment stability. A sensitivity analysis was conducted to evaluate how changes in key parameters affect system efficiency. This work shows that geothermal culvert deicing offers a sustainable approach to winter maintenance by improving soil resilience and reducing long-term infrastructure deterioration in cold climates.