PSI - Issue 24

Bosso et al./ Structural Integrity Procedia 00 (2019) 000 – 000

10

Nicola Bosso et al. / Procedia Structural Integrity 24 (2019) 692–705

701

CT − Light axle − box 22 Z" [m/s2]

Tasca42axle − box 11 Z" [m/s2]

4

10

9

3.5

8

3

7

2.5

6

2

5

4

1.5

percentile 99.85

percentile 99.85

3

1

2

0.5

1

0

0

− 1

− 1

− 2

− 3

− 2

− 4

− 5

− 3

− 6

percentile 0.15

percentile 0.15

− 4

− 7

− 8

− 5

− 9

− 10

− 6

30

32

34

36

38

40

42

29

31

33

35

37

39

41

43

Travel distance [km]

Travel distance [km]

2

10

1.8

1.6

8

1.4

6

1.2

1

4

0.8 rms value

rms value

0.6

2

0.4

0.2

0

0

30

32

34

36

38

40

42

44

29

31

33

35

37

39

41

43

Travel distance [km]

Travel distance [km]

a)

b)

Fig. 10. Percentiles (0.15% and 99.85%) and r.m.s. values of the coach vertical accelerations measured on the Gotthard base tunnel on the CTLIGHT (axle-box 22) and TASCA (axle-box 11) vehicles, passing on the switch section on the diverging route (km 37).

During the test, a camera was fixed on the coach and synchronized with the acquisition system, in order to relate the results with the track defects and singularities. The camera has been oriented to record the track and one wheel of the coach. From the analysis of the video at about the km 37, where the acceleration peak was detected, it is possible to notice the presence of a series of railway switches that is the cause of the acceleration increment. Fig. 11 shows the first railway switch located at the km 37.

Fig. 11. Detail of one vehicle wheel while running on the switch located at km 37 of the Gotthard Base tunnel.