Structural behaviour of concrete structure under the axial load with respect to rust formation computed at the AI-support

Abstract

The present study concerns the finite element modelling of structural behaviour for concrete structure subjected to the axial load and simultaneously corrosion of steel embedment. The structural capacity was expressed into the risk of cracking with respect to the compressive and tensile stress, while a development of steel corrosion was reflected by the increasing rust formation on the steel surface. To consider the buffering capacity at the steel–concrete interface against stress generated by the rust formation, the interfacial gap was taken, of which the width accounted for 10 µm. As a result, it was found that the tensile deformation could occur with only the axial load, which can be further developed by the rust formation. Also, the compressive deformation took place at the steel–concrete interface, arising from the steel corrosion, which had been marginally affected by the axial load. At the steel–concrete interface, the risk of cracking was strongly dependent on the position, due to the offset-effect of stress. Moreover, the compressive strength of concrete had a crucial impact on the risk of cracking, in particular, the compressive cracking could be adversely mitigated by the lower strength of concrete.