Incorrect Bending Capacity reported for Single Angles designed as per Canadian Steel Design Code CSA

First Affected Version:
 Found in Version:
Fixed and Released in Version: 
 Area: Steel Design as per CSA S16-09/14
 Issue #:1093383

Problem Description

Bending capacities for Single Angles designed as per CSA S16-09 or CSA S16-14 are being calculated incorrectly by STAAD.Pro. This error affects flexural capacity calculation for both equal and unequal angles.The CSA S16-09 and S16-14 specifications, does not provide specific guidelines on the determination of the bending capacity of single-angle sections. In absence of such guidelines, STAAD.Pro uses corresponding expressions from Clause No. F10.2 of the AISC 360-05 (for CSA S16-09) and AISC 360-10 (for CSA S16-14) codes, for the evaluation of the bending capacity of single angle sections. However due to a coding error, the expression was improperly implemented in the program, due to which the bending capacity was being over-estimated leading to an unconservative design of single angle sections.



No workaround is available as of now for this defect.


The defect is being addressed and a fix will be available in the upcoming STAAD.Pro CONNECT Edition V22 Update 5, scheduled to be released during the fall of 2020.