Pre-Eng Metal Building 4

[txdilbert]

Guys,

Have a customer that wants to erect an 80' x 60' x 20' pre-engineered metal building on an existing 100' x 100' monolithic concrete slab to control cost. Core samples suggest the slab was poured at 12" thick(?), with no reinforcement. Unclear what type of concrete mix was used.

Since the customer is adamant about avoiding unnecessary site work, a cost engineered solution is in order. I'd definately like to hear how folks on this site might approach this project. Suggestions?

 

[dik]

You need a geotekkie... depends on the soil and climate conditions. Pre-eng metal buildings have a little ductility and since they are basically 'throw away' structures the fates may smile on you...

Dik

 

[hokie66]

I would run a mile to get away from this. You can't put a 20' high building on a pavement slab.

 

[dik]

Slab is 12" thick... and thrusts diminished a tad due to the height... I've done them with stiffened edges and 5" slab in the middle... overall mass would be less.

Dik

 

[hokie66]

But unreinforced? Have at it.

 

[Ron]

Cut the slab, place footings and move on.

 

[msquared48]

Or underpin.

Pro lem will be the tension tie.


Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[frv]

Agree with Ron. Just cut the slab and place the footings. If owner objects, point him to the yellow pages and wish him good luck in finding another engineer.

 

[PMR06]

This client may be willing to skimp on his building now, but I doubt he will skimp on lawyers when something goes wrong in the end!!

I would show the client objective reasons it should not be done (unknown rebar & conc mix, frost depth issue?, unknown bearing, etc). If he still insisted, then I would professionally walk away from the job.

Good luck!

 

[Brad805]

I bet he is anxious to pay your fees too. I suggest passing on the opportunity to work with this client.

 

[JedClampett]

Concrete slab and foundation work is extremely cheap. If they are scrimping on that they should be working out in the open or in in their trucks. In addition, no reputable PEMB manufacturer would put their structure on an undesigned foundation. But lucky for your client, there are many disreputable PEMB suppliers.
If your client needed their appendix removed, would they try to save money by having it done in their living room? Doing favors like this for clients is what causes engineers to lose their licenses.