The mechanical performance of pedestrian structures attracts the attention of several studies, especially with respect to unfavourable operational conditions or possible damage scenarios. In terms of vibrations, for example, specific customer comfort levels must be satisfied, depending on the class of use, the structural typology, the involved materials, in addition to basic safety requirements. A special consideration should be given to in-service systems that are possibly affected by degradation or even damage, and thus potentially unsafe for pedestrians. In this regard, the availability of standardized non-destructive protocols for a reliable and rapid structural safety assessment may result in efficient support for diagnostic analyses. In this paper, 3 different laminated glass (LG) modular units belonging to 2 different indoor in-service pedestrian systems located in Italy are investigated. Operational Modal Analysis (OMA) procedures and dynamic identification techniques are used to quantify the residual capacity of the examined systems, including damage and material degradation, based on a single triaxial Micro Electro-Mechanical System (MEMS) accelerometer. The experimentally derived performance indicators and calibrated mechanical parameters for the examined structural system are assessed towards traditional design procedures, and further quantified with the support of Finite Element (FE) numerical model updating. A comparative analysis is carried out to explore the structural performance and safety levels of in-service LG slabs in regards to vibration comfort, deflection control and stress analysis.

The main goal of Anti-Shatter Films (ASFs) applications for structural glass is to create a barrier able to keep together fragments and minimize risk after any impulsive or static load that could lead glass to cracking. The influence of ASF properties on the flexural strength of coated glass elements is thus a relevant topic for safe design purposes, but still little investigated. To this aim, an experimental material investigation is presented in this paper, in order to achieve a good knowledge of common ASFs from a chemical point of view. Moreover, the deterioration of mechanical and adhesion characteristics for ASF samples subjected to different environmental conditions and accelerated ageing is also investigated, so as to simulate the effects of long-term exposure to high humidity (HU) or high temperature (HT). An experimental campaign carried out on 20 small scale ASF-coated glass specimens is finally presented, based on a three-point bending (3PB) test setup. The out-of-plane bending response of unaged or aged samples is performed by taking into account two different displacement-rate levels, to assess their performance and bending capacity under steady-static or impulsive loads. In both cases, the attention is given to the characterization of elastic and post-failure performances. Finally, support for the interpretation of experimental outcomes is derived from a simplified theoretical model of composite beam with partial connection, in order to estimate the shear stiffness of ASF adhesive components in the elastic stage.

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).

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This paper investigates the column buckling behaviour of three-layer Cross Laminated Timber (CLT) panels under compression, from both the experimental and numerical point of view. The main aim of present study is hence to define the expected load-bearing capacity for these composite CLT solutions, and to assess the typical fracture mechanism for two different series of specimens of possible technical interest for construction applications. To this aim, a total of 14 column buckling experiments is carried out. First, a set of 7 homogeneous speciemens (“HO” series), which are entirely made of beech, are investigated. Their load-bearing capacity is compared with the column buckling performance of 7 hybrid specimens (“HB” series), whose inner layers are made of Corsican pine. Overall, the experimental analysis gives evidence of a rather stable column buckling capacity for CLT panels, with evidence of major failure mode due to out-of-plane bending phenomenam, but also rolling shear and delamination. Finally, further assessment of experimental evidences is provided by extended analytical calculations (based on existing formulations, including the Eurocode 5 approach) and even Finite Element (FE) numerical analyses for the examined three-layer CLT compositions. Comparative results are discussed in terms of structural performance, capacity, weakness of analytical models for CLT solutions.