Product(s):	SACS
Version(s):	All
Area:	Post

Problem

When comparing SACS output on both ISO 19902 (2007) and ISO 19902 (2020) discrepancies were found in the unity check as below. 

   

Solution

It can be seen from the Details Report that changes happen in the combined axial tension, bending and hydrostatic pressure check.

  

                   ISO 19902 (2007)                                                                ISO 19902 (2020)

The relevant changes can be seen in Section 13.4-2, equation 13.4-7 in ISO 19902 (2002) as below:

                                                                                    ISO 19902 (2007)  

                                                                                    ISO 19902 (2020)

This explains the reduction in the reported unity check and since this does not actually affect the allowable stress calculation it does not show in the reported values apart from the unity check. 

          

See Also

See in comparison 13.4-13 and 13.4-19 for compression, bending and hydrostatic pressure in ISO 19902 (2007) and ISO 19902 (2020)