A NOVEL HETEROGENEOUS LIMIT ANALYSIS TOOL WITH STEREOTOMY FOR THE ASSESSMENT OF MASONRY CURVED STRUCTURES

Recent advances in computational tools and experimental validation are driving innovations in the preservation and analysis of double curvature masonry structures. With such a need in mind, this study presents an integrated workflow combining parametric modeling (PoliBrick plugin) and Finite Element Limit Analysis (FELA), focusing on failure mechanism and collapse multiplier triggered in curved masonry structures subjected to vertical loads. The PoliBrick plugin, developed for Rhino software by two of the authors, is used to parametrize and generate three-dimensional masonry assemblages of bricks where stereotomy is accounted for, which are then integrated in finite element limit analysis. Limit Analysis is dealt with the Upper Bound (UB) theorem and by means of a heterogeneous approach, where blocks are assumed infinitely resistant, and joints are reduced to interfaces with rigid-perfectly plastic behavior. While current confidence in vertical load resistance for modern buildings does not directly apply to historic masonry structures, limit analysis provides a practical, rapid estimation of collapse loads. To validate it, a benchmark study is presented, by analyzing a masonry arch for which previously numerical and experimental results are present in the literature. Results obtained show the efficiency and robustness of the proposed method in predicting the ultimate load-bearing capacity of curved masonry structures, by highlighting the functionality of the PoliBrick plugin in UBLA (Upper Bound Limit Analysis). The framework proposed provides enhanced accuracy for limit analysis, revealing insights into failure behavior under gravitational loads.