False floor replacement for corroded API 650 tank base plate

[davidribeiro]

An existing tank has a base plate which has corroded to the point where the product is leaking into the soil underneath. Due to enviromental issues, we need to replace this base by raising the floor (for ispection) by means of ribs / webs. API 650 does give equations to calculate the distance between these webs, and the thickness of the new base plate.
Can anyone tell me how to size the flat bars supporting this base & also how to check for buckling of these webs?

 

[JoeTank]

The system of support beams should be checked for lateral load resistance (for wind and earthquake forces) as well as web crippling due to vertical compression of the web. The procedure for web crippling should forllow AISC procedures. For wind and earthquake loads it will be too complicated to go thru here.

Steve Braune
Tank Industry Consultants

http://www.tankindustry.com

 

[MJCronin]

david,

As I recall, many leaking flat-bottomed tanks are repaired by constructing a second bottom above the first.

The space between the two bottoms is filled with sand and is monitiored for leakage. Wouldn't this be a better solution for your tank ?

Can you tell us more details about your particular application ?

MJC

 

[davidribeiro]

The client had asked for this configuration. I think they even explored the option of a concrete florr on top of the corroded base, but because of expansion issues and the clearance between the concrete and the shell, they opted for the above mentioned config.

ThanksMJC...