The span by span, stage constructed, pre-stressed concrete box girder bridge, known as the Denny Creek Viaduct, was instrumented during construction with Carlson gages. This report describes information on long term creep and shrinkage strains, and on live load and thermal strains collected using those gages in a two-year period starting approximately two years after completion of the bridge. Relevant literature on creep and shrinkage deformation predictions, live load stress predictions, and thermal load predictions for stage constructed bridges is reviewed. The predictions of accepted state- of-the-art procedures are compared with the strains and temperatures recorded by the Carlson gages. Significant temperature gradient strains, caused by diurnal temperature changes, are reported. A procedure is developed for predicting meters and design scenarios recommended for critical temperature events. The stage constructed cross- section responded to live loads similarly to a homogeneous section. However, tension strains still existed in regions where compression strains were predicted as a result of creep and shrinkage effects.
August 13, 2007
Neil M. Hawkins, John H. Clark.
University of Washington. Dept. of Civil Engineering.
- # of Pages: 296 p., 5,519 KB (PDF)
- Subject: Box girder bridges, Creep, Deformation, Highway bridges, Investigation of structure, Live loads, Prestressed concrete bridges, Shrinkage, Strain gages, Strain (Mechanics), Stresses, Thermal stresses, Viaducts.
- Keywords: Bridges, box girders, live load stress, thermal stress, creep, shrinkage, Denny Creek Viaduct, I-90.
- Related Publications:
This abstract was last modified April 29, 2008