Calibration of Bridge‐Strength Evaluation Code

The process of determining the live‐load capacity of existing bridges is distinct from the design procedure, which is necessarily generalized for applicability to a large variety of structures. Such a generalization may lead to overconservative estimates of capacity, which in turn leads to such actions as closing or replacing the bridge. Thus there is a great need for a flexible evaluation strategy which rationally accounts for all the uncertainties present while at the same time allows incorporation of engineering judgement and also maintains an adequate level of safety. Stuctural reliability principles with recently developed load models and extensive statistical data for all aspects of the problem is used to attain this goal. A load and resistance factor type checking equation is developed with options for different levels of traffic severity, lateral load distribution methods, degree of deterioration of structural elements, level of inspection, and type of maintenance efforts.