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Evaluation of thermo-mechanical and thermal behavior of full-scale energy foundations

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Abstract

Eight full-scale energy foundations were constructed for a new building at the US Air Force Academy. The foundations are being used to demonstrate this technology to the United States Department of Defense and have several experimental features in order to study their thermal–mechanical behavior. Three of the foundations are instrumented with strain gages and thermistors, and their thermo-mechanical response during a heating and cooling test was evaluated. For a temperature increase of 18 °C, the maximum thermal axial stress ranged from 4.0 to 5.1 MPa, which is approximately 25 % of the compressive strength of concrete (estimated at 21 MPa), and the maximum upward displacement ranged from 1.4 to 1.7 mm, which should not cause angular distortions sufficient enough to cause structural or aesthetic damage of the building. The end restraint provided by the building was observed to change depending on the location of the foundation. The heat flux per meter was measured by evaluating the temperatures and flow rates of a heat exchanger fluid entering and exiting the foundations. The heat flux values were consistent with those in the literature, and the foundation with the three continuous heat exchanger loops was found to have the greatest heat flux per meter. The transient thermal conductivity of the subsurface measured using the temperatures of the subsurface surrounding the foundation ranged from 2.0 to 2.3 W/mK, which is consistent with results from thermal response tests on energy foundations reported in the literature.

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References

  1. Adam D, Markiewicz R (2009) Energy from earth-coupled structures, foundations, tunnels and sewers. Géotechnique 59(3):229–236

    Article  Google Scholar 

  2. Amatya BL, Soga K, Bourne-Webb PJ, Amis T, Laloui L (2012) Thermo-mechanical behaviour of energy piles. Géotechnique 62(6):503–519

    Article  Google Scholar 

  3. Bjerrum L (1963) Allowable settlement of structures. In: Proceedings of European conference on Soil Mech. and Found. Engr., Wiesbaden, Germany, vol. 3, pp 135–137

  4. Bourne-Webb PJ, Amatya B, Soga K, Amis T, Davidson C, Payne P (2009) Energy pile test at Lambeth College, London: Geotechnical and thermodynamic aspects of pile response to heat cycles. Géotechnique 59(3):237–248

    Article  Google Scholar 

  5. Bourne-Webb P (2013) An overview of observed thermal and thermo-mechanical response of piled energy foundations. European Geothermal Congress. Pisa, Italy. 8 p

  6. Brandl H (2006) Energy foundations and other thermo-active ground structures. Géotechnique 56(2):81–122

    Article  Google Scholar 

  7. Brettmann T, Amis T (2011) Thermal conductivity evaluation of a pile group using geothermal energy piles. In: Hryciw RD, Athanasopoulos-Zekkos A, Yesiller N (eds) Proc GeoCongress 2012 (GSP 225). ASCE, Reston, VA, pp 4436–4445

  8. Energy Information Administration (EIA) (2008) Annual energy review. Report No. DOE/EIA-0384(2008)

  9. Gao J, Zhang X, Liu J, Li K, Yang J (2008) Numerical and experimental assessment of thermal performance of vertical energy piles: an application. Appl Energy 85(10):901–910

    Article  Google Scholar 

  10. Hamada Y, Saitoh H, Nakamura M, Kubota H, Ochifuji K (2007) Field performance of an energy pile system for space heating. Energy Build 39(5):517–524

    Article  Google Scholar 

  11. Hernandez R (2011) Geotechnical investigation report. Construct shower/shave facility. United States Air Force Academy, Colorado. Terracon Consultants Inc, 34 p

  12. Hughes PJ (2008) Geothermal (Ground-Source) heat pumps: market status, barriers to adoption, and actions to overcome barriers. Oak Ridge Nat. Lab. Report ORNL-2008/232

  13. Kavanaugh S, Rafferty K, Geshwiler M (1997) Ground-source heat pumps—design of geothermal systems for commercial and industrial buildings. ASHRAE. 167 p

  14. Knellwolf C, Peron H, Laloui L (2011) Geotechnical analysis of heat exchanger piles. J Geotech Geoenviron Eng 137(12):890–902

  15. Laloui L, Nuth M, Vulliet L (2006) Experimental and numerical investigations of the behaviour of a heat exchanger pile. Int J Numer Anal Methods Geomechan 30:763–781

    Article  Google Scholar 

  16. Laloui N, Nuth M (2006) Numerical modeling of some features of heat exchanger pile. Foundation Analysis and Design: Innovative Methods (GSP 153). ASCE. Reston, VA. pp 189–195

  17. Lennon DJ, Watt E, Suckling TP (2009) Energy piles in Scotland. In: Van Impe WF, Van Impe PO (eds) Proceedings of the 5th international conference on deep foundations on bored and auger piles, Frankfurt. Taylor and Francis, London

  18. Loveridge F, Powrie W (2012) Pile heat exchangers: thermal behaviour and interactions. Proc ICE Geotechn Eng 166(GE2):178–196

    Google Scholar 

  19. Loveridge F, Powrie W (2014) 2D thermal resistance of pile heat exchangers. Geothermics 50:122–135

  20. McCartney JS, Murphy KD (2012) Strain distributions in full-scale energy foundations. DFI J 6(2):28–36

    Google Scholar 

  21. McCartney JS, Rosenberg JE (2011) Impact of heat exchange on the axial capacity of thermo-active foundations. In: Han J, Alzamora DE (eds) Proc. Geo-Frontiers 2011 (GSP 211). ASCE, Reston VA, pp 488–498

  22. Mimouni T, Laloui L (2013) Towards a secure basis for the design of geothermal piles. Acta Geotechnica. doi: 10.1007/s11440-013-0245-4, 12 p

  23. Murphy KD (2013) Evaluation of thermal and thermo-mechanical behavior of full-scale energy foundations. MS Thesis. University of Colorado Boulder, 136 p

  24. Murphy KD, Henry K, McCartney JS (2014) Impact of horizontal run-out length on the thermal response of full-scale energy foundations. In: Abu-Farsakh M, Hoyos L (eds) Proc. GeoCongress 2014 (GSP 234). ASCE, Reston, VA, pp 2715–2724

  25. Ooka R, Sekine K, Mutsumi Y, Yoshiro S, SuckHo H (2007) Development of a ground source heat pump system with ground heat exchanger utilizing the cast-in place concrete pile foundations of a building. EcoStock 2007. The Richard Stockton College of New Jersey, pp 1–11

  26. Ouyang Y, Soga K, Leung YF (2011) Numerical back-analysis of energy pile test at Lambeth College, London. Geo-Frontiers 2011, Dallas, TX, pp 440–449

  27. Sanner B (2001) Shallow geothermal energy. GHC Bulletin. June Issue, pp 19–25

  28. Sanner B, Hellstrom G, Spitler J, Gehlin SEA (2005) Thermal response test—current status and world-wide application. World Geothermal Congress. Antalya, Turkey

  29. Skempton AW, MacDonald DH (1956) Allowable settlement of buildings. Proceedings Institute of Civil Engineers. London, Part 3, vol 5, pp 727–768

  30. Stewart MA, McCartney JS (2013) Centrifuge modeling of energy foundations under cyclic heating and cooling. ASCE J Geotechn Geoenviron Eng, 11 p. doi:10.1061/(ASCE)GT.1943-5606.0001061

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Acknowledgments

Support from DoD ESTCP project EW-201153 is gratefully acknowledged, as are the contributions of the 819th Air Force RED HORSE Squadron, who provided support for the heating test. The views in the paper are those of the authors alone.

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Authors and Affiliations

  1. Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, 428, Boulder, CO, 80309, USA

    Kyle D. Murphy & John S. McCartney

  2. Department of Civil Engineering, United States Air Force Academy, Colorado Springs, CO, 80840-6232, USA

    Karen S. Henry

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  1. Kyle D. Murphy
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  2. John S. McCartney
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  3. Karen S. Henry
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Correspondence to John S. McCartney.

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Murphy, K.D., McCartney, J.S. & Henry, K.S. Evaluation of thermo-mechanical and thermal behavior of full-scale energy foundations. Acta Geotech. 10, 179–195 (2015). https://doi.org/10.1007/s11440-013-0298-4

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