Optimization Method for Solving the Reasonable Arch Axis of Long-Span CFST Arch Bridges

Table 3

Stability coefficient of the first four instability modes.

Modal order	Instability mode	Parabola	Catenary	Spline curve
First mode	Symmetrical transverse	18.78	19.01	19.25
Second mode	Antisymmetrical transverse	22.15	22.73	22.84
Third mode	Symmetrical transverse	30.17	31.28	31.28
Fourth mode	Antisymmetrical transverse	35.55	35.74	35.92