Temporary removal of vertical bracing

[Amr Abdelhalim]

There is an existing steel pipe rack which there are 3 levels of vertical bracing.

The lower level of one direction vertical bracing in one span have to be removed temporarily for one week to allow a crane to enter to do a job there, is it safe to do so? No wind speed there and it is hard to re-evaluate the original calculation design.

 

[JLNJ]

It sounds like you need to hire a structural engineer to do some calculations. It should be pretty simple to evaluate.

 

[dik]

You should provide alternate bracing while you do the work.

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

-Dik

 

[SWComposites]

Is the rack empty or filled with pipe?

 

[271828]

A structural engineer needs to be evaluate this situation. I'm aware of project in which a structure had lateral bracing removed and collapsed with multiple fatalities.

No wind. It seems to have experienced story buckling.

 

[LittleInch]

Is the bracing asking the line of the rack or across the line.

A drawing would help but you have a lot of other forces in a rack than just wind.

Forces from the pipes are a major element as well as thermal expansion of the rack itself.

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

 

[Amr Abdelhalim]

I attach a drawing with highlighted the required bracing to be removed

 

[LittleInch]

So this is a cross section along the rack? Or a longitudinal part picture?

I'm guessing a cross section as the TOS levels vary. What spacing are the columns? Is it just one bay you're taking out or several?

Is there room to add a bracing to right and left of the red circle? I.e. move your removed bracing a few metres right and left?

How wide a gap in the section do you need? Can you install temporary vertical supports either side of the gap you need for the crane?

Plenty to think about for the structural engineer....

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

 

[Amr Abdelhalim]

This is a cross section along the rack however this bay is unique.

The spacing is 5.70 m and I am talking about this bay only.

Shifting bracing will be difficult to execute.

My question was preliminary as a concept, I shall create a model for the structure and re-evaluate the members before and after removing the required bracing.

 

[LittleInch]

So are the bays free standing on does this bay share a vertical member between it and the bay to the left?

How big a hole do you need for the crane? Presumably less than 4 m high, but how wide? Could you put slightly bigger knee braces in at the corner?

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

 

[le99]

I don't see the temporary removal of bracing will cause much problem. You should consider vacating the level immediately above too.

 

[JoshPlumSE]

I believe there is an ASCE guideline or code for temporary structures. Frequently used for concrete forming and construction related issues. It gives some guidance as to what level of lateral loads need to considered.

It is likely (IMO) that you will not need any temporary bracing as there are 3 other brace frames in the direction of the removed braces. However, it would be a good idea to obtain a copy of that code/guideline to justify it.

 

[Lomarandil]

Josh is referring to ASCE 37. It's set up for North America, but should be generally applicable to most conditions in low-seismic countries like Egypt.

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just call me Lo.