Fundamentals of Bridge Maintenance and Inspection

Bridges, including those on local roads, are integral elements of our highway systems. Despite
their importance, however, they are often the most neglected components of the infrastructure.
Demands on limited resources, especially competing roadway priorities for increased capacity
and improved riding surfaces, too often result in deferred maintenance for bridges. The
consequences are obvious -- bridges are deteriorating far faster than they are being repaired.
Without adequate attention, many require replacement or closure long before they are really
obsolete, further adding to the demand for limited funds, impacting safety, and discouraging both
users and transportation providers.
 
Establishment of national bridge inspection standards and New York's Uniform Code of Bridge
Inspection (NYCRR Part 165), both requiring that all structures more than 20 ft long be
inspected at least once every 24 months, have reduced the likelihood of catastrophic failure by
mandating appropriate followup after structural or safety citations. However, inspection cannot
slow down deterioration; merely identify it -- only properly scheduled, periodic maintenance
activities can retard deterioration. Studies have shown that preventive maintenance is a cost-
effective investment, and that deferring it only adds to bridge life-cycle cost.
 
This manual is intended as a handy reference for cyclical preventive-maintenance and
corrective preventive maintenance activities applicable to state and local bridges. 
 
The objectives of behind the manual are: 1) an education on bridge anatomy and those elements
requiring periodic inspection, 2) familiarization with the difference between elements
functioning as designed and those that are not, 3) identifying maintenance activities that can keep
elements functioning as designed for longer periods, and 4) providing repair and rehabilitation
options to return elements exhibiting severe deterioration to serviceable condition. A secondary
goal is to provide guidance for bridge owners in responding to structural or safety citations
(commonly called flags) resulting from inspections. 
 
This manual is designed to address the most common types of bridge distress by outlining
practical procedures for