NUMERICAL MODELLING OF BOND BEHAVIOUR IN RC STRUCTURES AFFECTED BY REINFORCEMENT CORROSION

Steel corrosion in reinforced concrete structures leads to severe degradation processes which usually affect both the ultimate and serviceability limit state performance of the whole construction. Numerical modelling of such a behaviour requires effective non linear models able to capture all the main effects of corrosion (i.e. cracking, reduction in bond strength, reduction in steel cross-section, bond degradation, etc.). This paper discusses these topics by focusing on the effects of corrosion on bond behaviour. In particular, a coupled mechanicalenvironmental damage model is used to simulate the deterioration of concrete (i.e. cover cracking and reduction of mechanical properties), while the effects of corrosion on bond behaviour have been dealt with using two different approaches, one based on a “frictional type” law and the other on a “damage type” law. A comparison between experimental pull-out test data and numerical results verifies that the proposed procedures can effectively simulate the effects of corrosion on bond behaviour, mainly for the “damage type” approach. Finally the numerical simulation of some experimental tests of corroded beam has been carried out.