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In 2018 a collaborative project between Politecnico di Milano (PoliMI) and Regione Lombardia (RL) was launched to join forces and expertise toward the improvement of the regional transport infrastructures maintenance management. One of the project goals was the development of regional guidelines aimed to support the design and implementation of monitoring systems for bridges. The focus of this paper is on the illustration of the Monitoring Regional (MoRe) guidelines and of their implementation on nine pilot monitoring systems designed and deployed within the project. The (MoRe) guidelines tackle the entire monitoring process from the analyses of the monitoring goals and the preliminary investigations needed to the identification of the phenomena and relevant indicators to monitor, up to the selection of monitoring devices and the presentation of results. A short illustration of the permanent monitoring systems installed on nine exemplary bridges in the Lombardia region concludes the paper. [ABSTRACT FROM AUTHOR]

In the framework of direct Structural Health Monitoring approaches, this paper presents a low frequency range analysis performed on a steel truss bridge designed in 1946 and built up in Northern Italy. The bridge is instrumented with a permanent structural health monitoring system, that guarantees a continuous flux of data and information from a heterogeneous set of sensors. In this analysis, static and quasistatic bridge responses are considered. These experimental data are merged with the analogous outputs obtained from numerical simulations, performed on FE models representative of the actual bridge, with the purpose of identifying damage‐sensitive indexes. Simulations are performed considering the healthy structure and modelling different damage scenarios. The static analysis consists in the construction of a regressive model able to estimate sensor output responses starting from environmental measurements, with the primary purpose to reduce the effect of temperature over measured static response. This procedure allows to relate the damages simulated by means of a numerical model with the real data, so that the monitoring rules can effectively defined. [ABSTRACT FROM AUTHOR]

The heritage of existing road infrastructures and in particular of bridges consists of structures that are approaching or exceeding their designed service life. Detrimental causes such as aging, fatigue and deterioration processes other than variation in loading conditions introduce uncertainties that make structural assessment a challenging task. Experimental data on their performances are crucial for a proper calibration of numerical models able to predict their behavior and life-cycle structural performance. In this scenario, an experimental research program was established with the aim of investigating a set of 50-year-old prestressed concrete bridge girders that were recovered from a decommissioned bridge. The activities included initial non-destructive tests, and then full-scale load tests followed by a destructive test on the material samples. This paper reports the experimental results of the full-scale tests conducted on the first group of four I-beams assumed to be in good condition from visual inspection at the time of testing. Loading tests were performed using a specifically designed steel reaction frame and a test setup equipment, as detailed in the present work. Due to the structural response of this first group of girders, a uniform behavior was found at both service and ultimate conditions. The failure mechanism was characterized by the crushing of the cast-in-situ top slab corresponding to a limited deflection, highlighting a non-ductile behavior. The outcomes of the experimental research are expected to provide new data for the life-cycle safety assessment of existing bridges through an extended database of validated experimental tests and models. [ABSTRACT FROM AUTHOR]