Effects of loading protocols on the seismic performance of non-structural drywall partitions

Non-structural drywall partitions, though non-load bearing, play a critical role in building functionality and post-earthquake recovery. Assessing their seismic performance is challenging due to their limited strength and deformation capacity, which makes them highly sensitive to the applied displacement history. Consequently, the differences in seismic damage assessment of these components under symmetric cyclic displacement protocols and ground-motion-derived displacement histories can be more pronounced than in primary structural components. This study examines how different loading protocols influence damage accumulation, deformation capacity, and post-earthquake conditions in non-structural drywall systems. To enable accurate damage assessment, a full-scale three-dimensional drywall assembly was tested under bidirectional intensifying ground motion, developed from scaled repetitions of a real earthquake record, using the six-degree of freedom Multi-Axis Substructure Testing (MAST) system at Swinburne University of Technology. Damage analysis was carried out to correlate lateral drift demands with observed physical damage states, followed by the development of fragility and vulnerability curves. The results were compared with the authors’ previous study on an identical drywall specimen subjected to quasi-static cyclic loading. The comparison showed a significant difference between the effect of symmetric cyclic displacement protocols and ground-motion-derived displacement histories on the damage states of drywall partitions. At the same drift levels, cyclic load resulted in more severe damages compared to the actual ground motion, directly influencing the resulting vulnerability and risk analyses. These findings highlight the need for future tests and the development of realistic loading protocols for non-load bearing drywall partitions to more accurately capture their seismic behaviour. • Effects of loading protocol on the seismic performance of non-load bearing drywall partitions are assessed. • Full-scale 3D bidirectional tests compared quasi-static cyclic (QSC) and sequential ground-motion (SGM) protocols. • The conventional QSC protocol resulted in more severe damages compared to the SGM load. • Fragility and vulnerability curves indicated higher failure probabilities under QSC-based limit states. • Findings highlight the need for realistic loading protocols in the seismic assessment of drywall partitions.