Earthquake performance evaluation of coastal structures

Environmental factors significantly affect the structural response of coastal structures. Therefore, it is necessary to account for environmental factors that could alter structural response while designing and analyzing piers. Corrosion is among the major factors that could affect structural behavior of coastal structures subjected to sea loads. In this study, the effect of corrosion on earthquake performance of a pier was investigated. Firstly, the phenomenon of the corrosion on metals in sea water was surveyed along with the corrosion models that are available in the literature. This was followed by the in-situ measurement of corroded metal thickness of steel jacketed composite piles. Compatibility of the measured corrosion data were then compared with those in the literature. A model was selected as the analysis model based on these comparisons. Earthquake performance analyses of the piled pier were made based on the selected corrosion model using equivalent push-over methodology. Reduced section values obtained from the selected corrosion model were utilized while determining sectional damage levels of the structural system, which were necessary for performance analyses. It was found upon conducted analyses that durability could significantly affect earthquake performance of the structure. As a result, an earthquake performance evaluation procedure taking into account of time dependent corrosion effect was put forward for coastal piers.