Mechanical Properties of Cement Material for Energy-Foundation (EF) Structures



Park, Yong-Boo;Choi, Hang-Seok;Sohn, Jeong-Rak;Sim, Young-Jong;Lee, Chul-Ho

  • 투고 : 2012.01.02
  • 심사 : 2012.01.19
  • 발행 : 2012.01.30


In this study, physical characteristics of cement and/or concrete materials that are typically used for energy-foundation (EF) structures have been studied. The thermal conductivity and structural integrity of the cement-based materials were examined, which are commonly encountered in backfilling a vertical ground heat exchangers, cast-in-place concrete piles and concrete lining in tunnel. For this purpose the thermal conductivity and unconfined compression strength of cement-based materials with various curing conditions were experimentally estimated and compared. Hydration heat generated from massive concrete in the cast-in-place concrete energy pile was observed for 4 weeks to estimate its dissipation time in the underground. The hydration heat may mask the in-situ thermal response test (TRT) result performed in the cast-in-place concrete energy pile. It is concluded that at least two weeks are needed to dissipate the hydration heat in this case. In addition, a series of numerical analysis was performed to compare the effect of thermal property of the concrete material on the cast-in-place pile.


Energy Foundation;Thermal Conductivity;Structural Integrity;Hydration Heat;Unconfined Compression Strength


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