NCHRP Project No. 12-28(7) is concerned with corrosion of superstructure metalwork of steel bridges. The primary objective of this project is to present practical field and office guidelines that can be used to assess the effects of corrosion on existing steel bridges. A description of the field and analytical investigations performed to develop these guidelines is included. Existing data were collected from many sources (in Task 1). These data were analyzed (in Task 2) and a framework for the development of corrosion inspection and evaluation guidelines was compiled. An interim report was prepared to present the findings of Tasks 1 and 2. Laboratory tests, field investigations, and analytical studies were conducted to complement the existing information. Based on the findings of these investigations, detailed guidelines for the inspection and evaluation of the effects of corrosion on existing steel bridges were developed. Field inspection guidelines for corrosion inspection of bridges are included in Part I of this report. These guidelines give corrosion inspectors background information on corrosion, the locations and forms of corrosion attack on bridges, and a suggested framework for corrosion inspection reports. Methods for office evaluation of corrosion effects in bridges are presented in Part II. They include simplified analysis techniques suitable for routine office evaluation. The office guidelines contain the necessary background for assessing localized and overall effects of corrosion on bridge structures. Effects of material loss, unintended fixities, and distortions caused by corrosion are treated in detail. Nondestructive evaluation techniques which may be applied to corrosion inspection are identified. Part III, the final part of the report, summarizes the methods of Part II in a guide specification format.
Samenvatting