Figure 1:

Figure 2:

Figure 3:

Figure 4:

Figure 5:

Figure 6:

Figure 7:

Figure 8:

Figure 9:

Figure 10:

Figure 11:

Figure 12:

Figure 13:

Figure 14:

Comparison of calculated and measured natural frequencies of tower portal No_ 906 V423
| Natural frequency - calculated | Natural frequency - measured | Deviation of natural frequencies | Description of the corresponding mode shape | ||||
|---|---|---|---|---|---|---|---|
| No. (j) | f(j) [Hz] | No. (j) | f(j) [Hz] | Expanded uncertainty Uk=2 [Hz] | Δ(j)[%] | ||
| 1 | 1.14 | 1 | 1.14 | ± 0.04 | −0.4 | ± 3.5 | 1st mode of horizontal bending vibration - direction X |
| 2 | 1.43 | 2 | 1.34 | ± 0.04 | 6.1 | ± 2.8 | 1st mode of torsional vibration |
| 3 | 1.78 | 3 | 1.74 | ± 0.04 | 2.3 | ± 2.2 | 1st mode of horizontal bending vibration - direction Y |
| 4 | 2.7 | 4 | 4.97 | ± 0.04 | −84.2 | ± 1.5 | 2nd mode of horizontal bending vibration - direction Y |
| 8 | 6.48 | 5 | 6.04 | ± 0.04 | 6.8 | ± 0.6 | 2nd mode of horizontal bending vibration - direction X |
| 9 | 7.88 | 6 | 7.17 | ± 0.04 | 9.0 | ± 0.6 | mode of hor. bending vibration of the left tower - direction X |
| 7 | 6.36 | 7 | 7.28 | ± 0.04 | −14.4 | ± 0.5 | mode of hor. bending vibration of the tower arms - direction X |
| 10 | 9.51 | 8 | 7.98 | ± 0.04 | 16.1 | ± 0.4 | mode of horizontal bending vibration - direction Y |
