GNGTS 2019 - Atti del 38° Convegno Nazionale

GNGTS 2019 S essione 3.2 677 Data processing and interpretation using HSSR analysis. The bell tower fundamental frequency was obtained using the HSSR technique (Horizontal Standard Spectral Ratio). The north direction of instruments was oriented parallel to the short side of the tower. The external measure “Est1” was used as (Fig. 1b) reference site. In figure 1c, d the location of the measurement points at each accessible level of the tower is shown. The instruments have been arranged along two vertical axis, maintaining the alignment between the floors taking into account the tower architectural constraints. Fig. 1 - (a) Location of Aci Castello municipality; (b) External sampling points; (c) Vertical 1; (d) Vertical 2.