Title: CALIBRATED FINITE ELEMENT MODELING OF CREEP BEHAVIOR OF PRESTRESSED CONCRETE BRIDGE GIRDERS

Author(s): Tanvir Hossain, Ayman M. Okeil, and C. S. Cai

Publication: Structural Journal

Volume: 111

Issue: 6

Appears on pages(s): 1287-1296

Keywords: construction sequence; creep; finite element method; structural health monitoring

DOI: 10.14359/51686974

Date: 11/1/2014

Abstract:
A three-dimensional (3-D) finite element model capable of predicting the long-term behavior of prestressed concrete girder bridges is presented. A temperature-independent creep model was adopted and calibrated using early-age data from embedded sensors in a girder while stored in the casting yard. Additional sensors were installed when the girder was later erected to be part of a newly constructed bridge that was then monitored for over 2 years to evaluate the performance of a newly adopted continuity detail. The calibrated model was run for 1000 days considering the construction sequence from the casting yard to bridge completion. Good agreement was observed between model-predicted axial strains and field data. Creep-induced restraint moments were evaluated for different girder ages at the time of establishing continuity and were compared to results obtained from other analytical methods. Finally, conclusions are drawn and a recommendation regarding the creep coefficient for predicting the restraint moment in prestressed concrete girder bridges is given.