Anchorage of corroded reinforcement – from advanced models to practical applications

Other conference contribution, 2015

When reinforcement in concrete corrodes, splitting stresses around corroded bars may lead to cover cracking and even cover spalling, affecting the anchorage. The aim of this paper is to give an overview on both advanced and practical models for anchorage capacity of corroded reinforcement which have been developed at Chalmers, and to show how these models can be applied in the assessment of existing bridges. The application of the practical model is exemplified in assessment of two bridges built in the 1960s. The bridges exhibit systematic damage in the form of spalled concrete on the bottom side of the main beams at cast joints where large amounts of reinforcement are spliced. The anchorage length needed to anchor the yield force was calculated from the bond-slip response, using the one-dimensional bond-slip differential equation. The model proved to be easy to use in practical design work. Furthermore, the bridges could be shown to have sufficient capacity, and costly strengthening could be avoided. This work clearly demonstrates the potential to certify sufficient loadcarrying capacity of corroded reinforced concrete structures through improved models.