FEM analysis of the response of masonry walls strengthened by traditional strengthening techniques

Evaluation of the appropriateness and effectiveness of the most used strengthening techniques is necessary to design seismic retrofitting. It is worth noting that in the case of historic masonry, due to its variability in materials and construction techniques, no general repair method exists; methods need to be appropriate to the masonry characteristics. For this reason, once a repair technique is proposed, it should be experimentally studied to understand not only the best application procedure, but also its effectiveness. Nevertheless, few studies are available on the efficacy of the various seismic-upgrading techniques employed to strengthen the masonry panels. Within this context, finite element models based on the smeared-crack approaches were developed to evaluate the shear resistance of masonry walls strengthened by reinforced plasters and grout injections. The capabilities of these models in capturing the strength and various failure mechanisms of such structures were examined, and crucial modelling considerations were identified by varying the thickness and the masonry texture types of the specimens. Finally, the feasibility of using the 3-Dimensional (3D) FE models for ultimate shear strength prediction was examined by comparing the results of experimental tests to numerical data.