Fatigue Durability of Partially Post-Tensioned Concrete Members
Freyssinet's original design concept for prestressed concrete maintained the concrete in compression under full service load [Billington, 2004; D'Arcy et al. 2003]. In fact, Billington  notes that “for Freyssinet, `the fields of prestressed concrete and reinforced concrete have no common frontier.' Either a structure is fully prestressed or it is not to be called prestressed concrete.” Prestressed concrete design has evolved over time to allow a nominal amount of tension in the concrete under full service load. Even with this nominal amount of tension, the design is still considered fully prestressed provided the tensile stresses do not exceed the modulus of rupture for the concrete. As part of the evolution of prestressed concrete, designers, code writers, and researchers have begun to examine the potential for utilizing even lower levels of prestressing that allow the concrete to crack under full service load. This type of prestressing is often referred to as partial prestressing. One of the primary reasons for the potential use of partial prestressing is that ultimate strength generally never governs the design of fully prestressed sections. Instead, the design is controlled by tension stress limits at full service load. However, that approach may be overly conservative, even with respect to serviceability concerns, if the full live load is infrequently reached during the life of the structure.
J. S. Volz and A. J. Schokker, "Fatigue Durability of Partially Post-Tensioned Concrete Members," Proceedings of the Structures Congress 2009: Don't Mess with Structural Engineers - Expanding Our Role, American Society of Civil Engineers (ASCE), Jan 2009.
The definitive version is available at http://dx.doi.org/10.1061/41031(341)169
Civil, Architectural and Environmental Engineering
Keywords and Phrases
Concrete; Durability; Fatigue; Post Tensioning
Article - Conference proceedings
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