Investigation of Deformation-Based Damage Limits of RC Columns for Different Seismic Codes

Deformation-Based Damage Limits

Abstract

The seismic performance of reinforced concrete (RC) columns is related to the expected damage limits under seismic loads and how this damage relates to the safety of the structure. Accordingly, the estimation of RC column deformations becomes more critical than the estimation of internal forces since the deformations in the post elastic regions of the structure are well correlated with damage in these regions. In order to assess the performance of RC columns under seismic loads, performance-based displacement and damage limits are proposed by certain codes. These limits are generally given for different damage and performance levels. Adequacy of the displacement and damage limit levels given in the codes such as Seismic Evaluation and Retrofit of Existing Buildings Standard (ASCE/SEI-41, 2017) and Turkish Building Earthquake Code (TBEC, 2018) were evaluated by carrying out parametric studies for RC columns. RC circular columns are designed in parametric studies to present the effects of various parameters such as concrete compressive strength, axial load levels and spiral reinforcement ratio on performance-based damage limits. Performance limits corresponding to each performance level obtained by different seismic guidelines were compared. It has been observed that there are significant differences in the results of the cross-section damage limit values of ASCE/SEI-41 (2017) and TBEC (2018), which can change the performance level of the building.