PSI - Issue 44

Caprino Amedeo et al. / Procedia Structural Integrity 44 (2023) 1578–1585 A. Caprino et al./ Structural Integrity Procedia 00 (2022) 000 – 000

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This outcome highlights significant density of points inside the urban area of Padova: considering a 61.9 km 2 AOI, the results define a MP density of 8310 MP/ km 2 and 10962 MP/ km 2 respectively for ascending and descending datasets. Fig. 2 (a) and (b) display mean LOS displacement velocity interpolated maps: both images show a low displacement rate in the city centre, where velocities tend to gather around null or slightly positive values; on the other hand, some other areas in the suburbs seem to be subject to displacements that move towards higher intensities of deformation. Fig. 2 (c) and (d) exhibit real displacement velocity maps, defined by expressions (1) and (2). As stated for LOS velocity maps, Fig. 2 (c) and (d) display very low displacement rates in the city centre, both for vertical and horizontal deformation, but more intense velocities appear on different areas in the suburbs and for infrastructures such as bridges and highways. Fig. 3 presents zooming views of the previous Fig. 2 in the area of the Scrovegni Chapel with a resampled pointwise distribution of displacement on a 7 m x 7 m grid. The mean LOS displacement velocity values presented in Fig. 3 (a) and (b) emphasize the idea of a stable condition inside the whole area, as none of the MP exceed the interval of relative stability, a range of LOS velocity values fixed at V LOS = ±1.5 mm/year that defines relative stable points (Tapete and Cigna, 2012). Moreover, Fig. 3 (c) and (d) highlight the presence of very low deformation rate also in vertical and in horizontal direction, which may be taken as a first clue of global stability inside the area and in the Chapel itself.

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Fig. 3. Displacement velocity pointwise distribution on Scrovegni Chapel and nearest surroundings: mean LOS displacement velocity of the ascending (a) and descending (b) dataset; real displacement velocity in the vertical (c) and horizontal (d) direction

Fig. 4 (a) displays the distribution of MP relative the Chapel and its surroundings for ascending and descending orbits; Fig. 4 (b) and (c) represent both 3-D distribution of MP and their mean LOS displacement velocity: the images permit to identify some clusters of points on the rooftop of the Chapel for the ascending orbit and on the entrance of the church for the descending one. As previously stated, mean LOS displacement velocities of the MP relative to the Scrovegni Chapel exhibit very low values and do not identify critical deformations on the monument.