Effect of infill walls on the seismic performance of a severely damaged substandard RC building during the February 6, 2023, Kahramanmaras earthquake sequence

• Published in: Engineering failure analysis 2025-03, Vol.169, Article 109117
• Main Authors: Tan, Mehmet, Avşar, Özgür, Yıldızhan, Fatih, Atmaca, Nihat
• Format: Article
• Language: English
• Subjects: Earthquake engineering; Infill walls; Reinforced concrete; Seismic performance
• ISSN: 1350-6307
• DOI: 10.1016/j.engfailanal.2024.109117

On February 6, 2023, two catastrophic earthquakes with moment magnitudes of Mw 7.7 and Mw 7.6 struck southern cities of Türkiye, occurring only nine hours apart. Spectral accelerations obtained from some of the recorded ground motions exceeded the design spectrum specified in the Turkish Building Earthquake Code (TBEC 2018) for the maximum credible earthquake level. This has prompted a review of seismic design practices within the framework of TBEC 2018. To address this concern, this study evaluates the performance of a reinforced concrete (RC) building with a ribbed slab that sustained heavy damage, according to official damage assessments, after the February 6th earthquake sequence. Numerical models were developed both with and without infill walls to assess their influence on the building’s response. Time history analysis and static pushover methods were used for its seismic performance assessment. Time history analyses were conducted under ground motions recorded at three different stations in close proximity to the investigated building. The inclusion of infill walls in the numerical model significantly influences the seismic performance analysis results. Peak floor accelerations of the building are determined to be higher at infilled model compared to the bare frame. The distribution of damaged columns in the actual building aligns well with the analysis results of the numerical model that includes infill walls. Notably, the numerical analysis using the ground motion record of the closest station to the building most accurately represents the actual damage distribution observed after the earthquakes. Finally, while the inclusion of infill walls in the model increases the lateral stiffness of the structure, it was also observed that displacement-dependent results obtained in the nonlinear time history analysis, such as relative story drifts, could increase depending on the selected ground motion record. This highlights the complex interaction between the infill walls, modal properties of the building, and the dynamic characteristics of the earthquake record. •Infill walls significantly affect the seismic performance of RC buildings.•Column damage distribution aligns well with the model including infill walls.•Accurate analytical modeling is crucial for achieving a reliable seismic response.•Including infill walls in the numerical model may amplify the seismic accelerations.