Cantilever AC Platform (Pullout Calcs)

[zero1238]

I have a client with a house raised on 18"x18" concrete columns due to being located within a flood zone. They are looking to attach an AC condenser platform to the sides of two columns, which will weigh approximately 2,000 lbs. As I'm not that familiar with these kinds of designs, how would you calculate the shear and pullout strength requirements for the concrete anchors if the platform was cantilevered 5' out from the column with that 2,000 lbs load right in the middle? Any guidance is very much appreciated. Thank you.

 

[JoelTXCive]

I would calculate the loads at the connection, and then download the Hilti or Simpson software. Unless you know the specifics of the concrete columns, I would select un-reinforced 2,500psi cracked concrete in the software.

Aside from the deadload of the equipment, I would assume a uniform live load too since a technician might stand on it when servicing.

If you are doing some brackets of some sort, then you can use elastic method for eccentrically loaded connection to get tension value at top and compression value at bottom of bracket.

 

[XR250]

As I'm not that familiar with these kinds of designs, how would you calculate the shear and pullout strength requirements for the concrete anchors if the platform was cantilevered 5' out from the column with that 2,000 lbs load right in the middle?

I assume from your question that you are not a structural engineer. I recommend hiring a local one to provide a design.

 

[zero1238]

That's a great idea. I just downloaded the Simpson software and I'm going to try setting it up right now. I appreciate the feedback, thanks!

 

[dik]

Be careful... 2000 lbs is about the weight of an old Volkswagon... nothing to fool around with.

Dik