	Applies To
	Product(s):	AutoPIPE
	Version(s):	2004, XM, V8i
	Area:
	Original Author:	Bentley Technical Support Group
	Date Logged & Current Version	Jan 2015 09.06.01.10

Problem:

Exactly how is AutoPIPE calculating the combined stress for a node point, equation used and individual values being applied in the equation?

Solution:

For Tresca stresses, AutoPIPE calculates stress from these three equations and uses the maximum value in subsequent equations:

SL1 = Axial (Neutral axis)

SL2 = Axial + Bending (Max Long if Axial is positive)

SL3 = Axial - Bending

These three values are used to calculate Tresca stresses using:

Similar approach is taken for Von Mises calculation.