Monitoring of Integral Abutment Bridges and Design Criteria Development

摘要

It has been observed that Pennsylvania integral abutment bridge behavior is much different from that predicted by current design methodologies. Thermally induced displacement magnitudes are typically on the order of 10 percent to 25 percent of predicted values. Thermally induced rotations and displacements are, in certain locations, opposite predicted rotations and displacements. Thermally induced stresses are not currently incorporated into design aids and guidelines and are not insignificant. Design methodologies must consider actual field observations such that the design accurately predicts the structural behavior. Proper application of integral abutments can then be made considering the findings of the study with new integral abutment bridge designs. In addition, PennDOT integral abutment design requirements will represent the state-of-the-art. The objective of the project was to revise and make more accurate integral abutment bridge design criteria based on observed structural behavior and results of numerical parametric studies. Observed behaviors were on the basis of field monitoring conducted at 4 integral abutment bridge sites and a weather station utilizing previously installed instrumentation and data acquisition systems. Integral abutment bridge engineering data were continuously collected over the entire contract period at bridges 109, 203, 211, and 222 and compiled, processed and evaluated. Numerical parametric studies were conducted on the basis of 2D and 3D finite element models, developed and calibrated to the observed integral abutment behavior, in order to evaluate the field performance of integral abutments and establish the range of potential applications for integral abutment bridge construction in Pennsylvania.