Numerical Derivation of Buckling Knockdown Factors for Isogrid-Stiffened Cylinders with Various Shell Thickness Ratios

Table 2

Properties of the detailed models for the isogrid-stiffened cylinders with various shell thickness ratios.

Thickness ratio, ()	536 (441)	356 (300)	244 (200)	122 (100)
Radius, (m)	2.250	1.530	1.020	0.510
Length, (m)	2.200	1.500	1.000	0.500
Length of resin ring, (m)	0.083	0.056	0.035	0.019
Length of a triangular unit cell, (m)	0.360	0.282	0.188	0.094
Height of a triangular unit cell, (m)	0.415	0.244	0.163	0.082
Thickness of stiffener, (m)	0.004	0.0027	0.0018	0.0009
Thickness of skin, (m)	0.004
Effective thickness, (m)	0.0042
Thickness of weld land, (m)	0.007
Depth of stiffener, (m)	0.008
Angle of stiffener,	60°
Elastic modulus, (GPa)	73.1
Poisson’s ratio,	0.33