PITA Fiscal Year 2011 Projects

Development Of Ultra High Performance Concrete Energy Pile Foundations

Lead University: Lehigh University
PI: Muhannad T. Suleiman, Department of Civil and Environmental Engineering
Co-PI(s): Clay Naito, Department of Civil and Environmental Engineering
PA Industry: Central Atlantic Bridge Associates and Nyleve Bridge Corp

Subsurface geothermal resources represent a great potential of direct usable energy. Deep foundations required to support structural loads that simultaneously work as heat exchangers represent a cost-effective, innovative sustainable technology that contributes to carbon dioxide emission reduction and protect the environment. Geothermal deep foundations (or energy piles) have been used to support buildings in Australia and Europe; however, well-documented cases of their use in the United States are scarce. Currently, concrete material is preferred for energy pile applications because of its high thermal storage capacity, and they are mainly installed using drilled shafts construction techniques, however, a recent survey reported that 76% of State Departments of Transportation prefer the use of driven piles to support bridges. Driven concrete piles, however, are susceptible to tensile cracking during easy driving and may fail in compression during driving in hard soil. To minimize drivability challenges and ensure durability of concrete piles, the use of Ultra High Performance Concrete (UHPC) piles was recently investigated by a research team led by the principal investigator of this proposal. As part of the research project, an H-shape UHPC pile was designed and based on field tests and drivability analyses it was concluded that UHPC piles can be driven using a wide range of hammers and strokes without suffering the problems observed in normal concrete piles. It is envisioned that UHPC energy piles will be developed and they will be used to support bridges. Energy piles supporting bridges will be used during winter to transfer heat to bridge decks to melt snow and prevent ice formation, which is expected to significantly reduce accidents and the loss of life. This proposal seeks funding for the initial phase of the project. At this stage, an initial phase and a proof of concept is being proposed. In this phase, fabrication and driving challenges of UHPC energy pile will be examined. Furthermore, preliminary field evaluation of the UHPC energy pile system and surrounding soil will be conducted.