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Accession Number PB2014-100626
Title Development of a Family of Ultra-High Performance Concrete Pi-Girders, December 2013.
Publication Date Dec 2013
Media Count 68p
Personal Author B. Graybeal G. Zhang L. Chen
Abstract Ultra-high performance concrete (UHPC) is an advanced cementitious composite material which has been developed in recent decades. When compared to more conventional cement-based concrete materials, UHPC tends to exhibit superior properties such as increased durability, strength, and long-term stability. Past research and deployment efforts have demonstrated that the pi-girder concept is viable from the structural design, fabrication, and construction standpoints. This computational investigation focused on developing a series of finite element optimized sections of UHPC pi-girders to effectively utilize the superior mechanical properties of UHPC over longer span lengths. The research was performed using the previously calibrated concrete damage plasticity model to represent the elastic and plastic response of the UHPC in the numerical simulation. The new cross-sections were developed based on the 2nd generation pi-girder that was previously tested in the laboratory. The cross-sectional parameters that were modified include girder depth, bulb width and height, web thickness, and the number of strands in the bulb. The analysis evaluated the local transverse bending capacity of the deck, the global flexural and shear capacity, and the deflection of the girder. Four cross sections with depths between 35 and 47 inches facilitating spans up to 135 feet are presented.
Keywords Composite materials
Cross sections
Finite element method
High strength concretes
Research and development
Ultra-high performance concrete(UHPC)

Source Agency Federal Highway Administration
NTIS Subject Category 50C - Construction Equipment, Materials, & Supplies
50A - Highway Engineering
Corporate Author Federal Highway Administration, McLean, VA. Office of Infrastructure Research and Development.
Document Type Technical report
Title Note Final rept.
NTIS Issue Number 1412
Contract Number N/A

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