A rapid seismic assessment framework for historic masonry walls: Influence of brickwork configuration, material deterioration, and numerically derived response factors

Historical unreinforced masonry (URM) walls exhibit highly diverse brickwork configurations and often suffer from progressive material degradation, both of which significantly influence their seismic performance. This study develops a comprehensive numerical framework to evaluate the in-plane behavior of historic masonry walls considering twelve distinct brickwork patterns and three levels of brick and mortar deterioration. Three-dimensional detailed micro-models were constructed, and advanced nonlinear analyses under combined vertical and lateral loading were performed. For each configuration, the capacity curves were bilinearized, and key seismic indicators, including response factor, ductility, amplification factor, energy dissipation, and failure mechanisms, were extracted, resulting in 36 fully characterized structural cases. Based on these extensive numerical results, allowable drift limits were proposed for historic masonry walls with different brickwork arrangements. Leveraging these detailed numerical results, a rapid and simplified seismic assessment framework was developed by transforming the three-dimensional nonlinear micro-model into a two-dimensional linear macro-model, with the effects of material deterioration incorporated indirectly through equivalent continuum properties. The proposed framework was validated against all 36 detailed micro-models, further verified using three independent studies with acceptable accuracy, and subsequently applied to two historic masonry walls to demonstrate its practical applicability. The comparison showed that the simplified macro-model generally reproduced the response of the detailed micro-models with close agreement. The proposed framework provides a computationally efficient approach for rapid preliminary seismic screening of historic masonry walls with different brickwork configurations and deterioration states.