PSI - Issue 42

Davide Leonetti et al. / Procedia Structural Integrity 42 (2022) 480–489 D. Leonetti et al. / Structural Integrity Procedia 00 (2019) 000–000

486

7

Fig. 6: Macroscopic fracture surface features, specimen TA690-4.

30

100

20

50

10

0

0

-50

Strain [ m/m]

-10 Strain [ m/m]

SG-B1-Week 1-Original SG-B1-Week 1-Detrended

31.14 31.142 31.144 31.146 31.148 31.15 Hours -20 SG-B1-Week 1-Original SG-B1-Week 1-Detrended

-100

-150

0

50

100

150

Hours

(a) week of measurement

(b) e ff ect of passing vehicle

Fig. 7: Strain signal acquired at the bottom flange of the girder in location B.

20

20

SG-C1-Week 1-Original SG-C1-Week 1-Detrended

0

10

-20

0

-40

Strain m/m

-10 Strain [ m/m]

-60

SG-C1-Week 1-Original SG-C1-Week 1-Detrended

-80

31.14 31.142 31.144 31.146 31.148 31.15 Hours -20

0

50

100

150

Hours

(a) week of measurement

(b) e ff ect of passing vehicle

Fig. 8: Strain signal acquired at the bottom flange of the girder in location C.

3.2. Simulated VA tra ffi c load history

Figures 7-8 show a comparison between the strain measurements due to passing vehicles at locations B and C. Due to the di ff erent influence lines a the two locations, the strain signals are significantly di ff erent, i.e. determining a positive o ff set for location B and a negative o ff set for location C. Both the strain gauge signals have been first detrended as described in Section 2.2, and are shown in Figures 7-8 as black lines. By comparing the original and the detrended signals it can be observed that the shape of the signal is preserved, and also the amplitude with respect to the strain value that is read without tra ffi c load.