This synthesis reports bridge inspection practices in the United States and selected foreign countries. The synthesis is a collection of information on formal inspection practices of departments of transportation (DOTs). These are primarily visual inspections and they provide data to bridge registries and databases. For U.S. inspection practices, this synthesis reports on inspection personnel, inspection types, and inspection quality control and quality assurance. Staff titles and functions in inspection programs are reported, together with qualifications and training of personnel, formation of inspection teams, and assignment of teams to bridges. Inspection types are described in terms of their scope, methods, and intervals. Quality control and quality assurance programs are reviewed in terms of the procedures employed, staff involved, quality measurements obtained, and the use of quality findings in DOT inspection programs. Foreign practices are presented in the same organization of inspection personnel, types, and quality programs. Comparisons of U.S. and foreign inspection practices are included. Information was obtained from a questionnaire sent to U.S. state transportation departments, similar questionnaires modified individually for transportation agencies in selected foreign countries, and formal documents used by transportation departments and agencies. These documents primarily included bridge inspection manuals, inspection training manuals, and technical memoranda, but also included blank forms for inspections, DOTs job descriptions for inspectors, and descriptions of inspection training courses. Overall, this synthesis includes information from forty U.S. state transportation departments and from roads agencies in eight foreign nations (Denmark, France, Finland, Germany, Norway, South Africa, Sweden, and the United Kingdom). The synthesis also includes, in an appendix, information from a few provincial and municipal transport agencies in Canada.

Improving bridge safety, reliability, and the allocation of bridge inspection resources are the goals of the proposed risk-based bridge inspection practices. Currently, most bridges in the United States are inspected at a fixed calendar interval of 24 months, without regard to the condition of the bridge. Newer bridges with little or no damage are inspected with the same frequency as older, more deteriorated bridges thus creating inefficiency in the allocation of inspection resources.The proposed methodology incorporates reliability theory and expert elicitation from the Indiana Department of Transportation's Risk Assessment Panel, developed during this research, to rationally determine bridge inspection needs. Assessments are made based on the likelihood and consequence of failure for specific bridge components. The likelihood of failure is determined through attributes based on design, loading, and condition characteristics while the consequence of failure is based on expected structural capacity, public safety, and serviceability. By combining the expressions of likelihood and consequence for each component, an optimum inspection interval for the entire bridge can be determined through the use of risk matrices.The methodology was evaluated through case studies involving Indiana bridges. Over 30 years of historical inspection reports were utilized in the back-casting process to evaluate deterioration levels and assess the adequacy of the risk criteria. Results of the case studies conducted during the research indicated that the risk analysis procedures provided suitable inspection intervals ranging from 24 to 72 months for Indiana bridges.

"TRB's National Cooperative Highway Research Program (NCHRP) Report 782: Proposed Guideline for Reliability-Based Bridge Inspection Practices presents a proposed guideline for reliability-based bridge inspection practices and provides two case studies of the application of the proposed guideline. The guideline describes a methodology to develop a risk-based approach for determining the bridge inspection interval according to the requirements in Moving Ahead for Progress in the 21st Century Act (MAP-21)."--Publisher description.

The New York State Department of Transportation (NYSDOT) maintains an inventory of over 17,000 highway bridges across the state. As per New York State's Uniform Code of Bridge Inspections, all bridges in New York State are inspected biennially, or more often as necessary. Bridge inspectors are required to assign a condition rating for up to 47 structural elements of each bridge, including 25 components of each span of a bridge, in addition to the general components common to all bridges based on visual inspection of these elements. The bridge condition rating scale ranges from 7 to 1, 7 being new and 1 being in failed condition. In addition to this, ratings 8 and 9 are assigned to cases "not applicable" and "condition and/or existence unknown". The objectives of this research have been to (1) conduct a detailed evaluation of the consistency of inspection ratings, and (2) provide recommendations for improvements to bridge inspection procedures and training to improve consistency, whenever possible. A broader outcome of the research has been the development of knowledgebase [sic] on factors affecting consistency of bridge ratings. These research objectives have been achieved through a detailed and comprehensive literature review on inspection practices and the NYSDOT bridge inspection program and, development and evaluation of consistency of the bridge inspection ratings through the inspection of 4 selected bridges by 21 inspection teams. Numbers of bridges and inspection teams have been selected to generate statistically sufficient data for the evaluation of consistency of inspection of different bridge elements. A detailed and quantitative evaluation of consistency of inspection ratings of different bridge elements has been carried out through the analysis of inspection data. Results show that the overall consistency of ratings of different elements is more than 90%.

The purpose of this manual is to organize, document, and combine Iowa Department of Transportation (Iowa DOT) policies and procedures for bridge inspection practices and post-inspection recommendations so Iowa DOT personnel, local agencies, and consultants will have a readily available resource for their use. Previously, bridge inspection policies and procedures were documented by various means, making it difficult to provide consistent answers to questions regarding bridge inspection topics. This manual is intended to ensure uniformity and document best practices for inspection of Iowa's bridges, especially as experienced inspection personnel retire.

Discusses techniques that require physical measurement for inspection, and/or monitoring of structures.