PSI - Issue 44

Alessandra Maione et al. / Procedia Structural Integrity 44 (2023) 1372–1379 Alessandra Maione et al. / Structural Integrity Procedia 00 (2022) 000 – 000

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method of limit analysis to the T-shaped masonry system, strengthened by CFRP grouted anchors, its horizontal capacity was derived from the prediction of the failure mechanism providing the minimum load multiplier. The novelty herein introduced regards an improved definition of the geometry of the possible failure mechanisms by considering the variable position of the hinge along the wall height in addition to the crack inclination angle. Moreover, a simplified approach based on a closed-form formulation was proposed for calculating the maximum stabilizing moment provided by the anchors. Such an approach was compared to the non-linear kinematic (NLK) one presented in the previous model and a good agreement was found in terms of both horizontal capacity of the strengthened system and geometry of the related failure mechanism. The key advantages of the proposed over the NLK approach are an easy and direct comparison among several design solutions and the need of knowing the only pull-out strength of the anchors instead of their whole load-slip law; on the other hand, the reduced number of the mechanical parameters limits the uncertainties of the assessment, enhancing its reliability. Then, the simplified approach was used to investigate several design strengthening solutions for a T-shaped masonry wall by parametric analysis and to identify the most suitable ones for a target performance representing the seismic demand (herein fixed as an increased capacity of the unreinforced configuration). In these analyses, the influence of the main geometric parameters affecting the contribution of both the anchors and the masonry system was illustrated. In conclusion, the proposed approach, herein used to assess the horizontal capacity against the rocking-sliding failure mechanisms of a T-shaped wall system, can easily be extended to façades with any number of orthogonal walls. However, an exhaustive evaluation of the horizontal capacity in the out-of-plane response should consider all the possible failure mechanisms for the strengthening system, as will be addressed in future works. Acknowledgements This work has been carried out under the financial support of the Italian Department of Civil Protection, within the ReLUIS-DPC 2022 – 24 Research Project. References Abrams, D.P., AlShawa, O., Lourenço, P.B., Sorrentino, L., 2017. Out-of-plane seismic response of unreinforced masonry walls: conceptual discussion, research needs, and modeling issues. International Journal of Architectural Heritage 11(1), 22 – 30. Casapulla, C., Maione, A., Argiento, L.U., Speranza, E., 2018. 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