A new discretized homogenization approach is proposed in this study in order to predict the behavior of unreinforced and FRCM reinforced masonry structures. The proposed approach allows overcoming the common disadvantages of the existing homogenization approaches: (a) being difficult to implement and (b) not allowing to couple the in-plane and out-of-plane actions. Reference experimental results and detailed numerical modeling are used for validation of the proposed modeling strategy. In the proposed model, the elastic cells are linked by homogenized interfaces. The mechanical properties coming from the homogenization procedures are lumped at the interfaces by means of the generic Concrete Damage Plasticity model, allowing easy implementation and avoiding computational issues peculiar to other approaches available in the literature. The new approach shows accurate results in predicting the global behavior and the damage pattern for both unreinforced and FRCM strengthened masonry walls. The results are promising also with a view to be applied for more complex reinforced applications as double curvature masonry structures. INTRODUCTIONThe heterogeneous character of masonry structures, along with their weak behavior under tension, make their analysis a challenging task. The need for introducing a reinforcing system, in order to reduce the vulnerability of masonry structures to seismic actions, adds a further complication in the numerical modeling procedures. A wide overview of the most diffused strengthening techniques used for improving the seismic performance of unreinforced masonry buildings is discussed in [1], which provides as well an insight into the numerical approaches used in literature. In the last five years, the application of fiber composite materials has met successively the requirements defined by guidelines, such as the ones from the International Council on Monuments and Sites. At first, after a successful application of FRP (Fiber Reinforced Polymer) on concrete substrates, the technology started to be applied also on masonry ensuring a marked increase in terms of strength and deformation, along with a relative easy execution [2]- [9]. Its effectiveness has been proved also at buildingscale level, an evidence supported by non-linear numerical analyses on case studies [10].In the case of interventions with FRP, the use of epoxy resins as matrix is able to provide an efficient bond with the masonry substrate. On the other hand, there are some disadvantages in terms of compatibility, as reported in [11]. The main issues are related to damp incompatibility, as the application of epoxies can be unsuccessful on humid surfaces. Also, the system masonry substrateepoxy matrix may be subjected to strain incompatibilities due to different thermal coefficients. Moreover, when applying this kind of reinforcement, the vapor permeability is strongly reduced. The issues are not only related to incompatibility with the substrate, but also to the potential of harm for workers when the epoxies are applied, to its hi...

This work focuses on an experimental and numerical study of a tuff barrel vault first damaged by differential vertical settlements of the abutments without rotations, then reinforced with a FRCM system composed by a fiber-reinforced mortar embedding a basalt fiber net, and finally subjected to a concentrated load on a generatrix (still ongoing). The geometry of the vault (polycentric near parabolic shape) and the masonry material (Apulian tuff) have been chosen in order to be representative of some masonry vaults common in rural constructions of Apulia region; also, a load representative of the infill weight has been applied during all the experimental tests. In parallel to the experiments, numerical simulations by a heterogeneous FE Abaqus model calibrated on the experimentally determined mechanical properties of materials have been performed. This model aims at reproducing the settlement phase and to accurately predict the load bearing capacity of the reinforced structure. To this aim, Concrete Damage Plasticity model has been used for modeling mortar joints and cementitious matrix, whereas tuff bricks have been assumed linearly elastic; finally, the basalt fiber net used in the FRCM reinforced has been described by suitable equivalent elasto-damaging trusses.

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The problem of the dynamic behavior of masonry arches and vaults has gained increasing interest in recent years, since the key role of these structural elements in the masonry constructions, especially of historic interest. Despite this, the literature still lacks a sufficiently large number of contributions on this important subject, and this deficiency is even more marked for the case of reinforced masonry. In this context, the present paper shows and discusses some preliminary experimental results on full-scale dynamic tests on unreinforced and GFRCM-reinforced Apulian tuff masonry arches. The experiments have been performed by using a test bench appositely designed and built; the dynamic excitation consisted of a harmonic base motion with fixed amplitude and increasing frequency. The acceleration in suitable points of the arches, the base shear and the base motion have been continuously monitored during the tests.