November 16, 2018

What is the Base Material Proration Factor?

The base material at the location of a weld may have less strength than the weld itself. In this case it will control the overall strength of the welded connection. In order to account for this, RISAConnection uses a weld strength reduction factor (α) which we call the Base Material Proration Factor.

This factor is a re-arrangement of AISC Steel Design Manual equation (9-2) which is presented as a thickness limitation.  In order to include this limitation in the capacity calculation, this equation is rewritten as a factor which is then applied to the weld strength calculation.

Per page 9-5 of the Steel Design Manual, this factor shall apply whenever the “available strength of the connecting element is not directly calculable”.  This is a subjective statement and we as engineers have done our best to include this factor wherever we thought necessary, such as a weld connected to the wall of an HSS column, or the web of a supporting column.

If you prefer not to include this factor, you can easily turn it off by unselecting the “Check Weld Base Mat. Thick” checkbox from the Solution tab of (Global) Model Settings.

Tags: ,

This entry was posted by RISA News on Friday, November 16th, 2018 at 10:15 am and is filed under Technical Solutions, What's New. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

Comments are closed.