Evaluation of Damage Limit State for RC Frame Based on FE Modeling

Abstract

Many damage limit states have been defined to characterize the extent of damages occurred in RC frame. Some of the damage limit states are defined by models that relate the limit states with the control points. Both control points and the limit state are expressed in term of response quantities. This research aims to evaluate the validity of such models by identifying the defined damage limit state with the corresponding damage based on FE modeling. The FE modeling provides a direct link between the damage and the response quantities. This link can be exploited as a basis for the evaluation. Based on the evaluation, this study proposed modified damage limit states. The response quantities with its corresponding progressive damage from FE simulation will also be used to inspect whether damage that can be expected to occur in the model structure is within the range estimated by the code based approach (CBA) damage limit state. Finally, fragility curves are constructed to assess the probability of the expected damage in the model structure under Design Basis Earthquake (DBE) and Maximum Considered Earthquake (MCE) scenarios. Utilizing the proposed damage limit states, the most probable damage in the structure falls in the category of slight if an earthquake at a level of DBE or MCE strikes the structure. However, at MCE level the probability of moderate damage attains 35%, or an increase by 23% compared to the DBE level.