Kazaz, İ.2026-03-262026-03-2620242-s2.0-105027866591https://hdl.handle.net/20.500.14901/4779Structural walls are vertical element of a system that is designed to resist seismic loads and considerable portion of lateral strength of a structure depends on the strength of structural walls. In Türkiye, the Mw 7.8 and 7.6 earthquakes on February 6th, 2023 caused a devastating effect on building structures over a very large region. The shear-walled buildings, mostly reinforced concrete moment resisting frames with shear walls, also suffered severe damage, particularly flexure-compression and shear-compression failures on structural walls, and some collapsed. The malpractice actions, such as seismic detailing neglected in workmanship of reinforcement, missing cross-ties in the boundary and web regions, incorrectly arranged web horizontal reinforcement end connection, insufficient lap splice lengths, reduced concrete strength due to aggregate segregation, that led to damage, are documented by field observations. However, as important as malpractice, there are some design factors that either fall short in providing the required strength and ductility to the wall members or were totally ignored as they are not present at the design stage. The letter factors can be listed as the wall index (ratio of wall area to building plan area), selection of structural form without reliable consideration of frame-wall interaction effects, large axial load variation on walls, beam to wall connection shape, the effect of large displacement excursions on walls due to near-field effects. It was identified that the most prominent cause of damage to the walls is low wall index. TBDY-2018 classifies structural system with structural walls according to the ratio of total wall moments to total overturning moment at the base. However, before TBDY-2018 the system definition is done according to the ratio of total wall shear forces to total base shear force. These two definitions produce quite different values for the wall index, which is lower for the letter classification. Most of the wall-frames structures, in which structural walls were significantly damaged, have wall indexes in the range of 0.2-0.4%. This study evaluates existing code design criteria on structural walls in the light of observed damage. A rational basis, which takes into account frame-wall interaction effects, is proposed to quantify the required wall index for controlled damage to wall member. Damage limits are proposed for the seismic performance evaluation of wall members. © 2024, International Association for Earthquake Engineering. All rights reserved.eninfo:eu-repo/semantics/closedAccessArticle