PSI - Issue 5

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Martini et al/ Structural Integrity Procedia 00 (2017) 000 – 000

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

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3.2. Sonic tests

The sonic tests were performed in the five PP1 to PP5 laboratory walls in accordance with the methodology described above. Some results are presented in Fig. 4 showing velocity spatial variability maps obtained in Surfer 13 Demo software (Golden Software, 2015). Ordinary Kriging was used as interpolation method, which is a geostatistical method mostly used for the so-called regionalized variables. It is possible to observe that the higher velocity points are those related with the direct test. The analysis of velocity maps in the stone masonry PP1, PP2 and PP5 (Fig. 3) allowed to confirm that the presence of the cross block (crosshatched block) can be identified by a local increase in sonic velocities. On the other hand, in stone masonry PP4 having no cross block and an irregular leaf, can be observed a disorganized behavior of the velocity contour lines. Even with a constitution of one irregular leaf, the existence of a cross block guaranteed a concentration of high velocity contour lines in PP3 wall. PP3

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Velocity maps (m/s)

Velocity maps (m/s)

Wall Typology

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Fig. 3: Sonic direct tests’ results .

Through the analysis of the results of indirect sonic tests (Fig. 4), it is possible to identify the influence of the joints on the velocity values, the velocities being reduced with the presence of the joints. By the analysis of the indirect results, it can be seen that the behavior of the waves, according to the presence of the joints, tend to vary. What is expected is that as joints are present, velocities tend to decrease, which is not confirmed by all readings of the accelerometers. The responses of the columns (1, 2 and 3) for all typologies had the same tendency. The first accelerometer went through only one joint, the second accelerometer passed through two joints, PP5 PP5

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