MecaStack considers effective length factors (K) for sections of a Self Supported or Guy WIre supported stack, depending upon the boundary conditions at each end of the riser section. The specific values used depend upon which stress code is selected; however, here is a summary of the factors used:

Cantilever:

Eurocode, Indian Code and BS 4076: K = 1.0

AISC 360 Code: K = 1.0 (This codes is used when STS is selected, but for small diameters STS refers to AISC. If we use a 2.0 factor then the stack fails nearly every time, and it seems very unrealistic; therefore, we use K = 1.0 which gives more realistic results).

All other Codes: K = 2.0

Pinned-Pinned:

All codes: K = 1.0

Pinned-Fixed or Fixed-Pinned:

Indian, BS 4076: K = 0.85

All other Codes: K = 0.8