×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Foundation Control

Foundation Control

Foundation Control

(OP)
Hi 1000$ for the correct answer:)
I d like to understand better the chapter 7.5.5.2 & 7.5.5.3 about foundations control before erection.
For 7.5.5.2 should we check only the contour?????It seems clear.
For 7.5.5.3 it talks about "specified high point" What does it mean?Is it an external point to refer to?
shall we check only the contour?Or the slope to?It is not very clear.

Thank you in advance

RE: Foundation Control

7.5.5.3 is for foundations whose top surface is not in a horizontal plane.  This is sometimes referred to as a "shovel slope".  In this case, the foundation has a high point and 180 degrees away is a low point.  The tank is installed vertical but the floor slopes from one side of the tank to the other.  When emptying the tank, the last bit of liquid will flow to the low side.  In all cases, a concrete foundation needs be + or - 1/8 inch from the required elevation in any 30 feet and + or - 1/4 inch from the required elevation for the entire circumference.  When the foundation is level, measuring deviations is easy since a single benchmark can be used.  When the foundation slopes it is a little harder but the concepts are the same.

RE: Foundation Control

(OP)
ok for a ringwall concrete foundation with internal slop  in sand...shall i follow chapter 7.5.5.2 or 7.5.5.3??

RE: Foundation Control

Since the ring wall is intended to be flat and level, you follow 7.5.5.2

RE: Foundation Control

(OP)
ok it is clear....i thought  to follow 7.5.5.3...yes, the ring wall is  a horizontal plane.
I m implementing a work instruction for the foundation check according to EN 14015 & API 650 for my company.

Thanks

RE: Foundation Control

Further thought TANKO, a 'level' tank floor will not drain due to all the lapped floor plates.  Crown the sand slightly to make the final dregs end up at the walls.  Or slightly depress the sand to have the dregs puddle in the center.

I like the center best -- easy for the Vac Truck to suck out the last liquid when cleaning the tank for entry.

RE: Foundation Control

Duwe6 - You are right - some slope is good.  API suggests 1 in 120 slope up to the center if the purchaser does not specify.  I think Tanko said there was a slope in the sand inside the ringwall.  I'm seeing more shovel bottoms now, not sure why - may be just a flash-in-the-pan.

RE: Foundation Control

(OP)
IFRs, it is correct what you say..there is a slope (3%)of sand towards the center inside the ringwall. We have erected 20 tanks near Rotterdam on this kind of foundation.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources