Storage Tank Foundation Rehabiliation 1

[JGard1985]

Has anyone repaired/rehabilitated an AST with a gravel foundation before? Without jacking?

The tank needs a new annular plates anyways so cutting open the floor for access is an option, just thinking about how to get good compaction up to the underside of the tank floor and tight to the shell wall.

What about grout?

I was also thinking of rehabbing with a concrete ring wall, obviously more costly but easier to control top of slab

Opinions/experiences appreciated,

 

[HTURKAK]

Pls look thread1452-465945 . If does not reflect your case, pls share some dtails for the subject tank ( dimensions, roof type,content, construction year...etc)

 

[LittleInch]

Well if it need rehabilitiation, this implies that the tank itself has moved / settled?

If so how much?

There's not much out there than can lift a tank as well as stabilise the ground in one go.

Needs some more details before anyone can advise more than just general stuff. There are many ways to skin this particular cat.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[JGard1985]

@ HTURKAK thank you for the thread, I'm reviewing that thread and a few others

@ LittleInch: Still determining the code of record...Settlement survey is part of the scope. The tank is founded on a gravel ringwall that has had some of the outer apron removed, half-fixes and potential undermining of the foundation. The annular plates need replacement, but need to address any degradation in the bedding underneath the foundation. I reviewed your posts in other threads regarding the slot technique to cut shell and insert annular plate lapped on top of the tank floor.

I'm considering a combination of slot cutting with removal of the existing annular plate to allow compaction of the ring wall

 

[LittleInch]

Any photos? drawings? ground surveys?

If it been there for a long time then it might be OK. Grout inject will do some good, but might create some hard spots.

A seriously accurate survey of the base plate or whatever you can find to see if it has in fact settled or not would seem like a good idea. If it ain't broke don't fix it.



Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[IFRs]

Grout or flowable fill is a reasonable remediation method. The annular plate should have complete and uniform support.

 

[JGard1985]

Thank you all for your advice. Looking forward to developing a suitable repair plan. Will let you know how it comes out!

 

[Gireesh123]

Dears,
Could you please advise whether Mn controlled(0.80% to 1.2%) material is compulsory for fabricating platforms and handrails for a fuel storage tanks or normal material with below 0.80% manganese is acceptable?.
Also pls let me know it has mentioned in API 650 standard, if Manganese controlled material required as said above.
Also pls let me know Grating and stir tread also to be MN controlled as per API650
I am expecting your valuable reply to my query. Thanks

 

[IFRs]

Out of respect for the original poster, next time please make a new thread instead of taking this one off in a different direction.

As far as API 650 is concerned, only materials for the tank shell and bottom plates under the shell need to be evaluated for toughness. When A36 is Mn controlled it goes from an API Group I to API Group II and can be used at lower temperatures for a given thickness.