Change I beam capacity change beta angel
Hello,
It is an expected result. For ratio calculation refer DG9 4.16b equation as shown below.
Here, sigmabx and sigmaby will flip for beta 90. Now as the denominator is not same for both the case, the end result will be different.
Though just seeing it seems that for a pipe section or SHS it will give same results in both direction, but it differs as per above equation.
Hope this clarifies.