Study on Dynamic Response Measurement of the Submarine Pipeline by Full-Term FBG Sensors

Table 1

Maximum working frequency of FBG strain sensor (strain wave is sine wave).

𝜆/𝑙0 (𝑛)	20
Effective length; 𝑙0 (mm)	20	25	30	40
Sensor is glued onto steel; 𝑓 (kHz) (𝜈=4500 m/s)	11.25	9	7.5	5.625
Sensor is glued onto plexiglass; 𝑓 (kHz) (𝜈=1700 m/s)	4.25	3.4	2.83	2.125
Sensor is glued onto concrete; 𝑓 (kHz) (𝜈=3500 m/s)	8.75	7	5.83	4.375
Sensor is glued onto rubber; 𝑓 (kHz) (𝜈=30 m/s)	0.075	0.06	0.05	0.0375