PSI - Issue 5

Rachel Martini et al. / Procedia Structural Integrity 5 (2017) 1108–1115 Martini et al/ Structural Integrity Procedia 00 (2017) 000 – 000

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thickness of the wall and half-wall. The indications with red arrows refer to the existence of hyperbolas that are associated with the horizontal masonry joints. Fig. 2 (b) shows the results of the tests also on the stone masonry PP4, but with the GPR/MALA and 1.6GHz center frequency antenna. These results refer to vertical and horizontal radargrams, spaced 2.5 cm. The research area this test was 50 cm high and 75 cm in length, centered on the position of the first cross block. The values obtained from these radargrams to the velocities of propagation of the wave, corroborate with the literature (Davis and Annan, 1989), which has v = 0,13m/s for materials like granite. In this figure, on a vertical wall radargram of PP4, identified with a blue line the end of the wall and a red line the interface between the two leaf. In the figures below, the x-axis corresponds to the thicknesses and the y-axis corresponds to the length of the analyzed walls.

PP1

(b)

PP3

(a)

Fig. 2: GPR radargram (a) 900 MHz antenna and (b) 1.6 GHz antenna.