Institute for Transportation

This report contains the findings of NCHRP Project 12-20, “Bridges on Secondary Highways and Local Roads–Rehabilitation and Replacement,” which was intended to develop information that local highway agencies can apply immediately to the repair, improvement, or replacement of deficient bridges on secondary and local road systems. Project 12-20 had four major objectives: (1) to identify the common deficiencies found on bridges on secondary highways and local roads throughout the United States, (2) to evaluate feasible corrective procedures that have been successfully employed for these deficiencies, (3) to evaluate economical replacement systems for bridge structures for which repair or rehabilitation is not feasible, and (4) to develop a simple procedure to assist engineers in making decisions involving repair or replacement. The major portion of this report consists of a manual of recommended practice–comprising 34 procedures for repair, rehabilitaiton, and retrofit of bridges and 27 systems that are available for use in replacing bridge components or complete structures. The manual is intended to be used by engineers responsible for bridges on secondary highways and local roads. In preparing the manual it was recognized that many of these engineers are not bridge specialists; therefore, the goal was to provide enough information to alert the engineer of his options in dealing with certain bridge deficiencies and to direct him to the proper sources for more detailed information required for a final design. The research agency’s complete, unedited final report on this study is included in the appendix. Background on the research approach and additional details are presented on the findings that led to the development of the manual.