07. How can I set the RESTRAINED pipe option for B31.8 2007 onshore / underground piping

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


How can I set the RESTRAINED pipe option for B31.8 2007 onshore / underground piping


Please see the following AutoPIPE help section:

Help > Contents> Contents Tab> Reference Information> Code Compliance Calculations> ASME B31.8-2007> Code Combinations 

Here you will see 2 charts displayed, restrained and unrestrained. Note that the combination's category will determine which calculators are used, i.e. restrained or unrestrained equations. Under the charts are a number of notes that you should review for a better understanding of AutoPIPE's analysis.

The calculations for restrained piping is conservative and assumes a small amount of contribution from bending, even on straight piping. The more restrained the piping is with more supports or higher soil properties the less contributions from bending and the closer to code calculations for St = E x alpha x (delta T).

In AutoPIPE v8i 09.06.01.xx., where piping code = B31.8 -2012 and higher, a new tab has been added to the Input grids to allow better control over the calculations for a section of piping (ex. A01 - A02) and data displayed in the output report. Please see the new Pipe Restraint tab where the user selects 1 of 3 options for each section of piping (i.e. unrestrained, restrained, Show both rest / unres). 


1. Another method of applying these values in a model is to use the following command, select a range of piping and then Insert> Xtra data> Piping restrained options. See AutoPIPE help for details on this command / dialog.

See Also

Bentley AutoPIPE