B31.1 Use of Eh vs. Ec

[jmmiller1206]

I am currently working with B31.1-2018 in CII v.12, project started before 2020 took effect and C2 isn't current w/B31.1-2020 as yet.

I understand flexibility calculations per B31.1 Para. 119.6.4 and 104.8.3 eq. 17 require Ec, but what about 104.8.1 Eq. 15 and 104.8.2 Eq. 16, or calculating reaction loads for supports and equipment? Is the use of Eh acceptable?

I see forum topics have been discussed, and stated that the B31 codes require Ec be used for flexibility analysis, however, I have not been able to locate a B31.1 reference stating or suggesting Ec should be used for flexibility analysis other than the calculation of Se (119.6.4). I am hoping someone will point me to a B31.1 reference that suggests the broad use of Ec for all stress and flexibility analysis? Mentioned forum discussions also referenced paragraph 319.5 of B31.3, which previously called for Ec to be used for pipe support load calculations, but was revised to state Eh should be used instead. What am I missing or is there a code case I need to refer to?

Thank you,

Josh

 

[XL83NL]

It seems to me 119.6.4 is the equivalent of 319.3.2.

Huub
- You never get what you expect, you only get what you inspect.

 

[KevinNZ]

119.6.4 is clear, Use E_C.
119.10 uses E_C to calculate R then correction using E_C & E_H to get R_H and R_C.

 

[jmmiller1206]

Thank you. I took more time to do further reading and for the code stress calcs Ec is required and for simple systems 119.10 may be used to calculate Rh and Rc.

I am moving forward with Ec load cases for 31.1 compliance and Eh for support and equipment load calcs.