Table 1: Natural frequencies and modal damping ratios of the SCB.

Vibration modes1st sym L1st sym V1st sym T1st anti-sym T

(Hz)0.1120.1860.5420.611
(Hz)0.1180.1950.5580.629
(Hz)0.1070.1850.5440.603

(%)3.653.241.231.26
(%)2.732.410.800.85

(%)−5.4−4.8−3.0−2.9
(%)4.50.5−0.41.3
25.225.634.932.5

Note: sym: symmetric; L: lateral; V: vertical; T: torsional; : frequency measured during Typhoon Fung-Wong; : frequency measured during normal wind; : calculated frequency based on FE method; : damping ratio identified during Typhoon Fung-Wong; : damping ratio identified during normal wind; = [( )/ ] × 100%; = [( )/ ] × 100%; = [( )/ ] × 100%.