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This paper aims at investigating the matrix-to-textile stress transfer in a fabric reinforced cementitious matrix FRCM system, not bonded to any substrate, under shear loads. To this end, direct shear tests are performed on a basalt FRCM specimen introduced into an innovative properly designed four-hinge frame loaded by a universal testing machine. The role of the single components in the global shear behavior of the FRCM is experimentally analyzed. Digital image correlation (DIC) is adopted for evaluating both the displacement and strain fields as well as for detecting the damage. Furthermore, the shear response of the tested FRCM material is reproduced via an effective numerical approach that considers the nonlinear behavior of the mortar and the possible micro-mechanisms that arise between the textile and the matrix, introducing suitable interfaces joining the FRCM constituent layers, i.e. textile and mortar layers. Experimental outcomes highlighted the non-negligible influence of the matrix in the shear response of the composite, both in strength and stiffness. The proven DIC technique demonstrated to be suitable also for this novel test type, since it allows to obtain shear strains, location and amplitude of cracks with satisfying accuracy, such as to make direct shear tests results a benchmark to be used for numerical simulations. Numerical analyses are performed in order to verify the efficiency of the proposed model in reproducing the mechanical behavior of FRCM composites under shear loads and in describing the damage patterns during the loading process.

Seismic events recently occurred in Europe highlighted the vulnerability of unreinforced masonry structures, representing the majority of the built heritage, to earthquake-induced loads. In particular, the in-plane capacity of shear walls under seismic loadings appeared sensibly modest, both in terms of strength and ultimate displacement, and their failure mode sudden and brittle. Textile Reinforced Mortar (TRM) composites proved to be a proper strengthening solution for the seismic upgrade of such walls. With the aim of gaining a deeper knowledge on the behavior of historical walls retrofitted with TRM and subjected to compression-and-shear, this paper summarizes the results of an experimental campaign characterized by quasi-static cyclic shear-compression tests. The specimens under study reproduced the rubble stone masonry typical of vernacular structures of the UNESCO historical district of Lyon (France). Specifically, the work concerns a full scale masonry wall tested under loading until the development of diagonal cracks and than repaired by a composite constituted by a basalt textile embedded in a lime mortar matrix applied onto the external surfaces as a plaster. The use of a lime mortar plaster to reinforce the structural element permits the development of a solution compatible with the historical substrate. Experimental outcomes revealed how Basalt TRMs succeeded in improving the response of damaged vernacular wall, both in terms of strength and displacement capacity.

The monitoring of the structural integrity of road and transport infrastructures, and in particular of bridges and viaducts, has now become a priority issue, emphasized by the progressive decay of the characteristics of building materials, and deterioration of the works, which can cause damage and collapses with dramatic consequences. Following recent bridge collapses, including the "Polcevera Bridge"in Genoa, Italy, the Ministry of Infrastructures and Sustainable Mobility (MIMS) issued in 2020 specific Guidelines on the classification and risk management, safety assessment and monitoring of existing bridges. In this context, the creation of information catalogues for the mapping of structures and the implementation of innovative procedures for monitoring, appear to be a crucial step for public bodies and managing bodies end of assessing the state of the civil structures such as bridges and identifying the priorities maintenance actions. To date, monitoring operations of bridges are typically conducted through visual inspections, coring and punctual measurements carried out by specialized operators and, more rarely, through the use of Non-Destructive Technologies (NDT). On the other hand, in recent years, satellite radar remote sensing techniques have always been applied much more effectively at monitoring infrastructures, civil works, bridges and viaducts. Among the modern techniques, Multi-Temporal Satellite Radar Interferometry (MT-InSAR) is currently established as a reliable tool for control and monitoring of deformation phenomena of the soil and large-scale infrastructures, capable of returning information with millimetre accuracy. Moreover, the knowledge about structural materials, structural elements and defect state of the bridge collected by onsite inspection, is crucial to verify the stability to actual traffic and dynamic loads, not expected in the design phases. This work reports a methodology useful for evaluating the viaducts and bridges stability at the network-scale level, proposing a multi-level monitoring protocol from the integration of information from different sources and technologies, including ground-based, structural and remote sensing information. The activities are carried out as a part of the "MLAZIO"project, approved and supported by the Lazio Region. The first phase of this project involves the creation of a vector database for bridges mapping and localization, and the development of an informatic catalogue for the management of works, also including a view of the geo-eGovernment of the infrastructures. Such a system is developed on a platform interoperable in a Geographical Information System (GIS), already prepared for the expected integrations in the later stages of the project, which includes on-site inspections, NDTs ground-based and satellite remote sensing investigations. This project aims to create a reliable and effective methodology for the risk assessment and management of existent bridges. This study paves the way for optimizing the planning procedures of the interventions of ordinary and extraordinary maintenance activities by developing a prototype for the development of a Bridge Management System (BMS) at a regional level, increasing the resilience of the investigated infrastructures and bridges.