Analyzing the Feasibility of Using Shallow Geothermal Energy to Prohibit Pavement Thermal Cracking: Field Testing
Amin Mohammadzadeh, Fereydoun Najafian Jazi, Omid Ghasemi‐Fare, Zhihui Sun
Abstract
This study provides insight into the application of geothermal energy to prevent thermal cracking in concrete pavements and bridge decks that may occur due to the high-temperature gradient. Two full-scale shallow geothermal boreholes were installed on the University of Louisville campus. U-shaped heat exchanger tubes were embedded inside both boreholes, and two demo bridge decks have been cast with concrete. Both geothermal boreholes are connected through a small trench to the demo bridge decks. A water/antifreeze mixture is circulated inside the heat exchanger tube, and the system solely depends on the constant ground temperature. Unlike the severe changes in ambient air temperature, the embedded tube showed an almost stable temperature. Temperature variations of the demo bridge deck connected to the geothermal borehole were limited and close to a near-constant ground temperature. Results confirm that a geothermal system can be used to cool the pavement surface even during hot summer days by reducing the temperature gradient in concrete, which may, in turn, reduce the risk of thermal cracking.