Evaluation of the seismic response of a historical earthen structure based on a discrete macro-element modelling approach

In the Peruvian Andes, a major portion of heritage buildings are made of adobe masonry. Due to the low mechanical properties of this material, historical constructions are mostly characterized by a weak and brittle behavior especially when subjected to seismic loading. In addition, heritage adobe buildings are characterized by timber roofs which do not guarantee a box-type behavior and enable the occurrence of local mechanisms in the out-of-plane direction. During the last decades, there has been an increasing interest in understanding the complex seismic response of this type of buildings. This task is usually conducted by means of computational models together numerical simulations. The current approaches such as Finite Element or macro-element methods present some important limitations such a high computational burden or over-simplified mechanical schemes that consider only the in-plane mechanisms of masonry. In this paper, an innovative numerical tool, which involves the combined interaction between the in-plane and out-of-plane mechanisms with a reduced computational demand, is used for the seismic assessment of an adobe church located in Cusco, Peru. This discrete macro-element modeling approach is validated considering the results obtained with a sophisticated computational tool in terms of capacity curves and collapse mechanisms. These results demonstrate that the proposed modelling approach is capable of properly evaluating the seismic behavior of earthen buildings, and will allow further investigations in a nonlinear dynamic context.