Issue 60

N. Hassani et alii, Frattura ed Integrità Strutturale, 60 (2022) 363-379; DOI: 10.3221/IGF-ESIS.60.25

After the cycle 10, particularly for specimens with the slenderness ratio equal 2 and 4, the attenuation of ultrasonic wave velocity is more notable. In case of specimens with slenderness ratio equal 1, the attenuation of ultrasonic wave velocity becomes notable after the cycle 16. When we compare the attenuation of specimens with slenderness ratio 4, 2 and 1 after aging process, the ratio UPV/UPVo equal respectively 0.2, 0.24 and 0.27. Although this difference is small, it still indicates that the h/b ratio has an effect on the behaviour of specimens.

a) Longitudinal measurements

b) Transversal measurements

c) Semi-direct measurements Figure 8: Time evolution of the UPV for specimen loaded with 70% of Rd according to the exposure conditions

Figure 9: Time evolution of the longitudinal UPV according to the specimen’s slenderness ratio h/b.

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