ACCOUNTING FOR EFFECTS OF CORROSION SECTION LOSS IN STEEL BRIDGES

A systematic, multiphase approach for evaluation of the effects of corrosion section loss on bridge capacity is presented. The first phase of the evaluation process is to identify the corrosion mechanisms, determine the extent of corrosion, and estimate the possible consequences. In addition to material loss, corrosion can cause unintended fixities, movements, and distortions and contribute to fatigue and fracture failures. The second phase of the evaluation process is a quantitative evaluation of corrosion effects. A two-level office evaluation approach is recommended. The Level I evaluation is based on simplified methods suitable for routine office applications. If needed, a Level II office evaluation that can demonstrate additional reserves in strength not taken into account in the original design may be used. To obtain a direct measure of the effects of corrosion section loss, a residual capacity factor concept is proposed. Using residual capacity factors, which are ratios between deteriorated and original member capacities, reduces the effects of other factors, such as the analysis method and the factors of safety used to determine capacities. Since the capacity of members affected by corrosion could be governed by modes of failure that did not control their original design, all likely failure modes must be addressed. The evaluation criteria need to include strength and stability, serviceability, and fatigue and fracture. Provisions for assessing the effects of uniform and localized corrosion with respect to strength and stability criteria are presented as an illustration of the proposed approach.

Language

  • English

Media Info

  • Features: Figures; Photos; References;
  • Pagination: p. 101-109
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00756077
  • Record Type: Publication
  • ISBN: 0309064694
  • Files: TRIS, TRB
  • Created Date: Nov 3 1998 12:00AM