Table 5: 1^st vertical, 1^st transversal, 1^st torsional natural frequencies and structural weight variation as function of the corrosion depth d, stiffness (1).

D (mm)	T (years)	f (Hz)
		1st Vertical	1st Trasversal	1st Torsional	G (kN)
0.00	1	2.53	2.58	3.03	1652.70
0.07	2	2.52	2.59	3.04	1649.17
0.15	3	2.51	2.59	3.05	1644.18
0.22	4	2.50	2.58	3.05	1637.71
0.29	5	2.49	2.56	3.05	1629.78
0.37	6	2.48	2.54	3.04	1620.39
0.44	7	2.46	2.52	3.03	1609.52
0.52	8	2.45	2.49	3.01	1597.19
0.59	9	2.43	2.46	2.99	1583.39
0.66	10	2.42	2.43	2.97	1568.12
0.74	11	2.41	2.41	2.95	1551.39
0.81	12	2.39	2.38	2.93	1533.18
0.88	13	2.38	2.36	2.91	1513.51
0.96	14	2.37	2.34	2.89	1492.38
1.03	15	2.37	2.32	2.87	1469.77
1.11	16	2.37	2.31	2.85	1445.70
1.18	17	2.37	2.32	2.83	1420.16
1.25	18	2.37	2.33	2.82	1393.15
1.33	19	2.38	2.35	2.82	1364.68
1.40	20	2.39	2.38	2.81	1334.73