The structural design of glass curtain walls and facades is a challenging issue, considering that building envelopes can be subjected extreme design loads. Among others, the soft body impact (SBI) test protocol represents a key design step to protect the occupants. While in Europe the standardized protocol based on the pneumatic twin-tire (TT) impactor can be nowadays supported by Finite Element (FE) numerical simulations, cost-time consuming experimental procedures with the spheroconical bag (SB) impactor are still required for facade producers and manufacturers by several technical committees, for the impact assessment of novel systems. At the same time, validated numerical calibrations for SB are still missing in support of designers and manufacturers. In this paper, an enhanced numerical approach is proposed for curtain walls under SB, based on a coupled methodology inclusive of a computationally efficient two Degree of Freedom (2-DOF) and a more geometrically accurate Finite Element (FE) model. As shown, the SB impactor is characterized by stiffness and dissipation properties that hardly match with ideal rigid elastic assumptions, nor with the TT features. Based on a reliable set of experimental investigations and records, the proposed methodology acts on the time history of the imposed load, which is implicitly calibrated to account for the SB impactor features, once the facade features (flexibility and damping parameters) are known. The resulting calibration of the 2-DOF modelling parameters for the derivation of time histories of impact force is achieved with the support of experimental measurements and FE model of the examined facade. The potential and accuracy of the method is emphasized by the collected experimental and numerical comparisons. Successively, the same numerical approach is used to derive a series of iso-damage curves that could support practical design calculations.

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The analysis of load-bearing capacity and the determination of blast protection levels for ordinary glass windows and façade components in buildings is known to represent a design and research issue of crucial importance. In the same way, reliable methods to address this issue are mostly based on cost and management expensive experimental investigations on full-size samples. According to the tendency of recent years, this paper presents some of major outcomes of Finite Element (FE) numerical methods and simulations that have been explored in the framework of the GLASS-SHARD research project for glass windows and facades under explosion or soft-body impact. The attention is focused on the analysis of a Triple Glass Unit (TGU), so as to address the blast performance of a rather ordinary glass window for buildings characterized by the presence of multiple laminated glass (LG) layers, on one side, and by the presence of two interposed gas cavities. The TGU blast performance is investigated in terms of load-bearing capacity of single components, with respect to variations in the input blast loads (stand-off distance R, charge W, etc).

Ancient masonry buildings are characterized often by a high seismic vulnerability: innovative intervention strategies for strengthening, based on the use of FRP composite materials are gradually spreading. In particular, the coupling of FRP preformed elements (meshes, angles and connectors) with mortar layers (Composite Reinforced Mortar techniques - CRM) evidenced a good physical, chemical and mechanical compatibility with the historical masonry and experimental campaigns proved to be effective for the enhancement of both in-plane and out-of-plane performances of masonry, contrasting the opening of cracks and improving both resistance and ductility. The resistant mechanisms that are created in CRM reinforced masonry walls subjected to in-plane horizontal actions are analyzed in the paper and a practical design approach to evaluate their performances is illustrated, evidencing the dominant collapse mode at the varying of the masonry characteristics. Some masonry walls are analyzed numerically and analytically, as “case study”.

Glass balustrades are designed to prevent large deflections and high stress peaks under conventional lateral loads. In practice, linear restraints are generally described in the form of ideal linear clamps for glass, to replace the actual geometrical and mechanical properties of restraint components. This means that strong simplifications are introduced in place of multiple details and components expected to offer local flexibility and prevent premature stress peaks in glass. In this paper, attention is given to linear restraints that are commonly described in terms of “clamp” boundaries for glass panels under lateral loads. The use of simplified mechanical models to characterize the actual stiffness and linear restraints and components is addressed, with the support of refined Finite Element numerical models and literature experimental data for balustrades under twin-tyre impact.