Thrust Layout Optimization for the Analysis of Historic Masonry Structures

Historic masonry structures form an important part of the world’s collective cultural heritage. Many methods have been developed for assessing the load carrying capacity of masonry gravity structures, from simple hanging chain representations to much more complex non-linear finite element models, though tools that can provide rapid and reliable assessments are still sought after. Here, a new automated procedure, termed thrust layout optimization (TLO) is presented. This is designed to overcome limitations of the traditional thrust line method, and more recently developed computer based alternatives such as the thrust network analysis (TNA) method. The new procedure is capable of automatically identifying admissible thrust lines in masonry gravity structures comprising general arrangements of masonry blocks, without the need to specify in advance the form of the thrust line or thrust network layout. As well as providing a rapid assessment of load carrying capacity, the TLO method provides a clear visual presentation of load paths. Also, sliding friction can be accounted for and large-scale problems involving complex geometries can be tackled, as demonstrated via various examples described in this contribution.