Special problems in evaluating the safety of concrete bridges and concrete bridge components

The safety and reliability of concrete bridges and bridges with concrete components depend on the ductility of reinforced and prestressed concrete, on the internal and external redundancy typical of concrete construction, and on concrete's demonstrated capacity to carry full design load while at the same time exhibiting severe cracking and the corrosion of embedded steel. These characteristics have formed the basis for effective and efficient inspection and evaluation procedures. Special attention may therefore be required when assessing the reliability of concrete bridges or bridge components whenever the design, configuration, material properties, or deterioration invalidates the underlying assumptions of ductility, redundancy, and the ability to carry load while severely cracked and deteriorated. It is recommended that bridge inspections and analyses begin with a review of these fundamental assumptions.