Expansion Joints in Big Box Buildings 2

[dengebre]

We have a single-story “big box” project in Florida that is 480’ x 160’. It was originally an all-steel building, with steel stud exterior walls, and using the Thermal Program (steeltools.org) it shows that an expansion joint is not required (Delta-T = 55 degrees). The project has changed to concrete masonry exterior walls and we are concerned that the restraint of the walls may now require an expansion joint. However, I recently went to my local Walmart Superstore (similar footprint) and they did not use an expansion joint. Are we being overly cautious?

 

[dik]

In 480' I would put a minimum of one expansion joint in the long dimension; I typically use about 250'-300' as a max length.

I don't know if it's codified; it's what I do.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[dold]

There is some guidance in AISC 360-10, page 2-39, fig 2-6, regarding expansion joints. There is also an Alex Tomanovich spreadsheet called "THERMAL.xls" that you can find on [URL unfurl="true"]https://www.steeltools.org/load.php[/url]. 480' is definitely big enough to look at expansion joints.

 

[dik]

Thanks, dold... good link.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[dengebre]

The Thermal program by Tomanovich is what I used, but my understanding is that it pertains to all-steel buildings only. I am still baffled as to how the Walmart Superstore down the street is the same size building and has no expansion joint.

 

[hokie66]

Does the Walmart building have masonry control joints? Not the same as a global expansion joint. Detailing of an expansion joint depends largely on the type of framing. If the building consists of rigid frames, you just need to provide a frame each side of the joint. If you are depending on a roof horizontal truss/diaphragm, then the problem is more complex.

 

[dik]

they should be at about 30' spacing...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[Aesur]

Here is a great article on expansion joints and includes other building materials as well: Link

 

[Aesur]

Also, I'm not sure if you have ever calculated the forces generated from thermal expansion of say a steel beam, but they are crazy high; without allowing for some movement, I expect you would see some issues over time in a building that long without expansion joints.

 

[dik]

I've never spliced bridging... I've always terminated it and used X-bridging in the adjacent panels.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik