capacity of conc section with correded reinf
capacity of conc section with correded reinf
(OP)
I may shortly be asked to compute the axial compression and flexural bending moment capacities of a reinforced concrete section with assumed amounts of the reinforcement "lost" through corrosion. That is, I know what the section looks like today, before any corrosion, and I'll be given the "amount" of corrosion in terms of steel weight lost. One approach would be to simply use the amount of remaining, non-correded steel in a standard analysis of RC section capacity (i.e. the bending capacity of a beam with 2 bars with 50% weight lost is equal to that of a non-corroded beam with one bar). But since the corrosion starts at the outside face of the bars, at the steel-conc interface, I wonder if the effects on bar bond are such that this "linear" approach isn't appropriate? Perhaps loosing (say) 20% of bar weight renders a bar completely ineffective. (Important detail: I'm told that the nature of the corrosion is such that the buildup of expanded, corroded material, which commonly spalls the concrete, isn't expected.) What approaches have the forum members taken? Thanks for any insights.






RE: capacity of conc section with correded reinf
RE: capacity of conc section with correded reinf
When loss of section occurs near the supports, the top steel is the primary concern, not the bottom steel. The stirrups also may loose section and bond - very difficult to see sometimes.
RE: capacity of conc section with correded reinf
http://ntl.bts.gov/lib/5000/5700/5737/ecfl.pdf
(Weight loss of 5% to 10% causes dramatic changes in rebar properties)
Here is a research paper, "Combined Effect of Corrosion & Stress in Reinforced Concrete Beams", that documents Dinosaur's comments
http://www.ce.utexas.edu/em2000/papers/KWang.pdf
www.SlideRuleEra.net
RE: capacity of conc section with correded reinf