Evaluating Redundancy of Two-Girder Steel Bridges

Cyclic loading can cause crack propagation within the tension elements of bridge girders. In an effort to detect and arrest large cracks before collapse can occur, the AASHTO LRFD Specifications require frequent inspections of bridges or bridge components that are identified as fracture critical.  Using lab tests, we are calibrating a finite element model developed in Abaqus/Standard to determine the redundancy that may exist in twin steel trapezoidal box-girders. If the structure is adequately redundant, it would be able to withstand a large-scale fracture without collapse, and inspection cycle times could be increased.