Versions of ASCE 7 for Section VIII, Division 1 Vessels

[dig1]

I'm wondering if anyone else has run into this situation.

Currently designing a vessel to the 2023 ed. of Section VIII, Div. 1. Table U-3 states that ASCE 7-22 be used. The jurisdiction where the vessel is going has adopted IBC 2018 (w/ some State specific amendments that do not apply for this discussion)that uses ASCE 7-16 as the building code. The structural engineer performing the foundation design, whose calculations need to be submitted to the Code Enforcement Officer (COE) as part of the building permit application, is saying that the loads from the vessel need to be according to ASCE 7-16. AI is saying 7-22. The only way I can see to make this work is run with both versions of ASCE 7 and use the higher of the two design results, which in this case is 7-16, and state that the loads from ASCE 7-16 exceed the minimum loads from ASCE 7-22. Additionally, going through the other appropriate sections of both versions of ASCE to verify conformance w/ both editions is required.

Obviously both the COE and AI will need to concur with this before a building permit is used for the vessel foundation and the AI signs the U-1.

Again, I'm curious if anyone else has run into this scenario.

Thanks

 

[AWDMIKE]

I have also run into this situation and I would guess it happens on occasion in the USA since ASCE 7 is the only environmental load standard referenced.

Updated local building codes may lag the IBC model code issuance by 1-2 years. If a project starts towards the end of a building code "lifespan" and then progresses or finishes during a subsequent building code "lifespan", the project may live to see two or more building codes and potentially two or more standard versions, including ASCE 7.

Several of the standards in Table U-3 say "latest edition" but some have specific years. It's possible that the standard is updated prior to a Code update, and I think there is either an interpretation or Code Case to address this matter, but there does not seem to be any provision to use an older standard. If it was a manufacturing standard, the requirement is understandable, but in this case ASCE 7 is a load standard and I believe there are instances where design loads increase or decrease with the newer standard. Even if an argument was made that "newer is always better", I believe the authority having jurisdiction may have to agree with this as well.

In the matter of whether to use the in-force ASCE 7 load standard of the one in the Table U-3, I do not know if the building code requirements override the ASME Code requirements.

 

[dig1]

Thank you AWDMIKE,

Fortunately we are doing both the vessel design for the fabricator and the foundation design so it is easier to handle the engineering aspect. Both the building code and ASME have what I consider equivalent legal standing in this instance. Maybe for the 2025 edition of the ASME U-3 can be re-worded to say "ASCE 7 adopted by the jurisdiction where the vessel will be located" or something similar. Code committee work is likely somewhat thankless and it is too easy for people (including myself) to complain; which I hope my question isn't taken as.