I-Beam on concrete pier

[Dogface]

Im planning to build a garage using concrete piers as a foundation. The piers will be sixteen inches in diameter.
To span the distance between piers l plan to use S 12x16 l beams. My question is, what it the best way to attached these beams to my piers? Would a simple weld plate, on top of the piers suffice?
Thanks in advance

 

[Focht3]

It depends a lot on the expected loads. Where is your site, and why are you using drilled piers? What does the reinforcing steel look like? Soil conditions? What controls the foundation design?



Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora.

 

[ERV]

What type of floor sytem will the garage have? And the walls? This sounds like an expensive way to build a garage.

 

[Dogface]

Thank you for the responses.
I am using piers instead of a stem wall due to the fact that the soil is quite expansive.I know l could use a standard pier and beam with void boxes but since lm doing this myself it would be much easier to put I-beams on top of piers and frame it up from there.I plan to have the piers drilled to ten feet,16" in diameter. A slab would be impractical due to the slope of the area. And I guess garage is not the correct word- more of a work shop. No car will need to be supported. Just the usual, tools and such.
So my plan was to put concrete piers (using sonotubes as needed) around the perimeter every ten feet, bolt an l-beam on top of the piers and frame the floor in much the same way a house is built.
l have observed that standard traffic light poles are bolted to concrete piers with four bolts. Would this be the best way to secure the beams? I have already built 1/2 inch by 8"x8" plates with three piece of number four rebar, about one foot long, welded to the bottom so that they will project down into the concrete. I had planned to simply place these into the concrete before it cures so that the plate just rest on top of the pier.(Of course l have also fabricated #4 rebar cages for each pier.) But now lm not sure if the plates are the right way to go. Will they transfer the load without cracking the pier? (I don't know if its relevant but the concrete will need to be pumped.)
Thanks again.

 

[Focht3]

Okay, where is your site? Expansive clays are one of my specialties, and the location is key to a reasoned response.

As a rule, the piers should have the smallest shaft diameter as practical, with a lot of continuous (unspliced) rebar steel. We typically use about 2 percent (no typo, guys) in the San Antonio area - a lot more than you need for normal shrinkage and axial loads. And you will need a full cage, not just a few bars jabbed into the concrete.

Sonotubes are great, but will the piers be deep enough? That's a key question - that I can't answer with the information you have provided...



Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora.

 

[DRC1]

I will let Focht 3 deal with the expansive soil because I don't know much about them and he does. As far as the beam goes, I haven't checked the loading, but if you are buying, usually "W" shapes are eaiser to wok with. The flanges are flat and thinner which makes it easier to drill and bolt. I would drill and grout 2-4 bolts at one pier (you can buy anchors and grout systems that are easy to use). After drilling the bolts, make a plywood template and transfer and drill the holes in the beams. On the other side drill in 2 bolts per beam and slot the holes slightly to accomidate minor movements of the steel
Good luck!

 

[Dogface]

I would drill and grout 2-4 bolts at one pier (you can buy anchors and grout systems that are easy to use). After drilling the bolts, make a plywood template and transfer and drill the holes in the beams. On the other side drill in 2 bolts per beam and slot the holes slightly to accomidate minor movements of the steel> DRC1

This is the information l was looking for. l was concerned that if l simply placed the beam on top of the pier it might somehow cause the pier to fracture. And yes, movement of both the steel and possibly the pier if the earth shifted was a concern.
Thank you for your response.
And to Focht3, thank you as well but l was really just trying to figure out how to attach the beam.