Residual Strain Monitoring and Dynamic Characteristics of Hybrid Hollow Square Tube with Metal–FRP–Metal Sandwich Walls

Table 5

Dynamic characteristics of the HSTs from the modal analysis module.

Characteristics	Steel–CFRP–steel	Steel	Relative difference (%)
Natural frequency (Hz)	1883	1974	−4.6
Damping ratio (%)	0.96	0.14	586
Weight (kg)	2.38	2.83	−15.9