Experimental investigations on the effects of the steel rebar corrosion at structural level

The paper presents some of the results obtained in the framework of a wide research program funded by the Italian Ministry of Instruction and Research, on the corrosion effects on existing structures. Both the aspects related to ultimate and serviceability states are analyzed. In particular, in the first case, the study is devoted to the definition of constitutive relationships of the steel rebars subjected to the corrosion. Many studies are available in literature on this topic, mainly with reference to the tensile behavior; the compressive one is generally neglected. The compressive and buckling behavior of corroded steel bar is discussed in this article with reference to experimental test results, and the importance of accounting for this peculiar aspect is motivated. Finally, with reference to serviceability states and based on tensile tests on reinforced concrete ties, the influence of corrosion on bond transfer length and crack pattern, due to low corrosion amount, not affecting the local and global strength, is clearly shown.