anchor bolt design calculation 5

[Rony_2012]

Hi All

I am doing anchor bolt Design calculation for vertical steel welded storage tank (11 meter high and diameter is 6.4 meter), so how do I calculate the load on each anchor? How to determine, like how many anchors bolt required for that? And what are the loads I have to calculate? Anyone have sample calculation for that?





Thank you

 

[IFRs]

See API 650 - the loads, load combinations, allowable stresses, etc are all there.

 

[HTURKAK]

- Min. No. of anchor bolts in this case , Π*D/3 = 3.14*6,4/3=6,69 round to nearest even number ⇒ 8 anchors..


- pls look API 650 section ( 5.12 Tank Anchorage ) .. for the load combinations ,allowable stresses pls look ( Table 5.21a—Uplift Loads (SI))



Tim was so learned that he could name a
horse in nine languages: so ignorant that he bought a cow to ride on.
(BENJAMIN FRANKLIN )

 

[dik]

Why round it to the nearest even number? Just curious? Often section modulus is improved slightly for odd numbers.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[JStephen]

Normally, a multiple of 4 is used, to straddle piping connections that might be located on the 90-degree lines.

 

[dik]

Thanks, didn't know that... even more interesting...

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[HTURKAK]

Addition to Mr JStephen comment,

- API does not use section modulus for polygon of anchors but uses the dia of the tank ( W=( Π*D**2)/4)

- It is a common practice to provide no. anchor bolts double , triple of no. of plates per shell course.. In this case, the no plates should be 4 and two anchors for each plate is OK.

- Even no.of anchors ( multiple of four ) is better to avoid clashes between anchor brackets and shell course butt welds ..

Tim was so learned that he could name a
horse in nine languages: so ignorant that he bought a cow to ride on.
(BENJAMIN FRANKLIN )

 

[dik]

Thanks HTURKAK... I would have thought that anchorage geometry would be used to calculate anchorage loads....

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[MJCronin]

I am guessing a bit here .... but based on your questions about calculating anchor bolt loads and number of anchors

I believe that you do not yet have a design for anchor bolt chairs .... Is that true ??

That topic has been discussed before on eng-tips

https://www.eng-tips.com/viewthread.cfm?qid=436024

https://www.eng-tips.com/viewthread.cfm?qid=2704

https://www.eng-tips.com/viewthread.cfm?qid=448340

https://www.steeltank.com/Publicati...id/all-publications-categories-1/Default.aspx

MJCronin
Sr. Process Engineer

 

[IFRs]

I seldom add anchors just to get an even number or multiple of 4 - why add cost for no substantive reason? If there are conflicts with piping, nozzles, etc. then maybe.

 

[Rony_2012]

Thans to all for your response and help
it would really help-full for me to calculate those loads and bit more knowing about the calculation and standards.

 

[dik]

Thanks IFRs... that's been my approach for decades... and I use the anchor locations, not the tank/stack.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[IFRs]

Rony - API 650 has load calculations and load combinations, anchor calculations and their allowable stresses. API 650 also tells you where to find calculations for the anchor chairs welded to the tank - AISI Steel Plate Engineering Data, Volume 2, Part 5, if you are using anchor chairs. If this is your first read of API 650 and designing anchors, straps or chairs, you really need to find someone in your organization with the expertise. Sure, you can use basic engineering principles and read API 650 cover to cover, then appy what you have learned and get answers for someone to review and check but ultimately it might be a far better use of your and your company's time to learn from someone who has done it before. The internet will only get you so far...and although we can point you in the right direction, it is not a slam-dunk simple and easy single-step calculation.

 

[MJCronin]

Whhhaaattttt !!!! .... Get some Geezer with experience to mentor and instruct the newbies ???!!! ...

Who would have thought ?????

MJCronin
Sr. Process Engineer

 

[human909]

What are you talking about MJCronin? What is a mentor? What is instruction?

The way people pass engineering courses today is by copying "example calculations" and repeating the same thing on exams. If they need help then then use textbook, lecture notes sample calculations. Further help from google and texting other students. Nobody talks to each other to find out how to do things. Let alone figure it out themselves from core principles!

MJCronin, I bet you are one of those crusty eningeers who actually can calculated things by hand and don't just copy example calculations! Pffft! So last generation!

 

[MJCronin]

Well, human .....

I probably am "one of those (old) crusty eningeers who actually can calculated things by hand"

.... but I did see a local dermatologist and the rash is clearing up nicely ...

MJCronin
Sr. Process Engineer

 

[dik]

Not enough fingers and I have a real problem with fractions... I still use my calculator.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik