Multi-parameters mechanical modeling to derive a confinement model for masonry columns

Increments of the axial capacity of existing masonry elements can be provided by confinement. Assessment methodologies with general validity to assess the behavior of confined masonry columns with strengthening systems are not available in the technical literature, in fact, the strong variability and heterogeneity of masonry material did not allow to develop generalized models. For brittle materials damage mechanics and failure criteria allow to do this in the framework of solid mechanics. However, the recent scientific researches provided relevant information about the experimental behavior of masonry confined with composites. In this paper, an analytical model able to assess the behavior of the confined masonry with composite is proposed. It was developed according to a failure criterion based on mechanical parameters representative of masonry. It can be applied to masonry cross sections of any shape also under a non-uniform lateral stress field (i.e. generic stress fields). To confirm the flexibility of the proposed model some existing experimental results have been used. The comparison between model predictions and experimental results in terms of axial strength showed that the proposed model is a valid tool to assess the confinement properties of strengthened masonry elements.