Material Behavior
Authors: Alireza Mohebbi (FHWA-Turner Fairbanks Highway Research Center) , Zachary Haber (Professional Service Industries, Inc.) , Benjamin A. Graybeal (Federal Highway Administration)
The use of ultra-high performance concrete (UHPC) for pretensioned bridge girders is appealing for bridge engineers due to its superior engineering properties. Design of pretensioned UHPC girders requires an accurate estimation of the prestress losses caused by creep and shrinkage. A review of the literature reveals a lack of information on creep and shrinkage behaviors of UHPC-class materials. As such, there does not exist an available model to estimate long-term prestress losses due to creep and shrinkage. The intent of this study is to address this gap. The main objectives of this research are as follows: (1) examine the current AASHTO equations for creep and shrinkage, (2) determine the applicability of parameters in the equations for UHPC-class materials, and (3) compare existing AASHTO models with measured creep and shrinkage of different UHPC-class materials. This paper briefly discusses existing models and the experimental research being conducted at Turner-Fairbank Highway Research Center to address the knowledge gaps.
Keywords: UHPC, Prestressed girders, Long-term losses
How to Cite: Mohebbi, A. , Haber, Z. & Graybeal, B. A. (2019) “Evaluation of AASHTO Provisions for Creep and Shrinkage of Prestressed UHPC Girders”, International Interactive Symposium on Ultra-High Performance Concrete. 2(1). doi: https://doi.org/10.21838/uhpc.9706