Instrumentation and Analysis of High-Performance Concrete Bridge Decks (05-1840)
Matthew D. D'Ambrosia, University of Illinois, Urbana-Champaign
David A. Lange, University of Illinois, Urbana-Champaign
Zachary C. Grasley, Texas A&M University
Jeffery R. Roesler, University of Illinois, Urbana-Champaign
Chang Joon Lee, University of Illinois, Urbana-Champaign
Salah A. Altoubat, University of Sharjah, United Arab Emirates

The use of High Performance Concrete (HPC) for transportation structures was the subject of a three-year study that involved field investigation, laboratory experiments, analysis, and modeling. The field study involved instrumentation and analysis of six HPC bridge decks. The laboratory component characterized early age thermal, shrinkage, creep, and cracking behavior. A 3-D finite element model was used in conjunction with material models to analyze and predict creep and shrinkage behavior and to investigate structural and material interactions. This paper focuses on the field component of the project and discusses the instrumentation, deformation measurements, and analysis of bridge decks in Illinois. The bridges were instrumented in an effort to understand the development of shrinkage and thermal stress in concrete bridge decks utilizing various materials and structural components. The results indicate that stress development due to daily temperature cycles and long-term temperature changes are relatively small when compared to drying shrinkage stress. According to model simulations, a 15 to 40 percent reduction in shrinkage would reduce the stress level enough to prevent most cracking. Although drying shrinkage is the major driving force for stress development, the interaction of concrete shrinkage and structural restraint influences the magnitude of stress and is linked to the propensity for early age cracking.