Dumpster Pad Design

[EngineeringEric]

Quick design, no budget to even ask this question here.

I have a small dumpster pad, its only design criteria is "support 10kip single wheel load". No soil information. I am coming up with 8" of plain concrete to support the load and then I will reinforce it with the minimum ACI steel at the top surface/middle.

Anybody do anything more or less for something of similar nature? Thanks

 

[mijowe]

I turn down the perimeter when erosion might be a problem

 

[racookpe1978]

When the dumpster is being picked up (by the garbage truck?) ...

Where is the expected (and real world) back tires of the truck going to be, and what will hold them up? What type of curb are you going to use to prevent the dumpster from getting "pushed" off of the pad when an idiot "pushes" it too far back/left/right?

 

[EngineeringEric]

This is an enclosed dumpster (Masonry walls). The pad is replacing a sidewalk and existing planted area. So the truck will be located on city streets during lifting.

The 10kips was provided by the dumpster company, so i assume it is maximum load from tires during lifting operations, but 10 kips is (or close) to road limit for single axle. We are also adding some bollards to the back of the dumpster to stop them from loading our wall when the guy hits drive instead of reverse.

Really i was just wondering if 8" seemed whole world wrong for something like this. I have done designs for heavy fire trucks and made my slab some 1'-4". But again it is a dumpster and all...

 

[Archie264]

Lacking exact site specific information a 6" slab with #4's at 12" e.w. will likely work. 8" almost certainly will. Your call though, of course.

 

[EngineeringEric]

Thanks for the input.

 

[ameyerrenke]

I've done similar analysis in the past, and i believe I came up with a similar result. I was assuming infinite edge distance, 4000 psi concrete, analyzed as unreinforced. If the pad may take loading near its edge it would be a good idea to turn down the edge as mijowe suggested.

 

[a2mfk]

I have used something like Archie's design with thickned edges for the CMU many, many times... 10 kip seems pretty extreme for your average dumpster unless it is one of those large construction dumpsters filled with concrete debris... Think about a dumpster enclosure, the truck never gets that close to the slab.

 

[TDIengineer]

8" seems too thick in my opinion for a dumpster. 10k wheel load each? I agree that sounds excessive. So your dumpster weighs 40k? or 20 tons?

Anyway, I would think a 6" slab would be more than adequate with a turned down slab.

 

[EngineeringEric]

The 10K was not my design value, it was what the dumpster company told me to design too. I thought 8" was too thick but for that load it is the minimum i could get to work... If was just designing a slab without the provided loads i would have went with a 6" in my guess... And this is why i asked the group for their insight on my design.

Really i think the over dimensions of the thing with a 2" thick than what we want will only be a cube of concrete, so the cost is maybe %100 for a more conservative design doesn't seem to be end of the world. I guess that is what happens if you want a cheaper design, you pay more in materials.

Thanks again everybody!

 

[madmantrapper]

Depending on the frequency of use, I have had them put in with #4 bars each way, 8" thick slab and steel wear runners on the surface to provide a wear surface. These wear for 30 and 40 yard roll offs for steel scrap.

 

[TLHS]

Yeah, I wouldn't even stress it. A slab like this is small in plan area, so it's a tiny amount of concrete. The few hours you'd spend trying to figure out a better design basis would likely end up costing you more than the materials.

 

[oldestguy]

I'd set the thickener for the height of the most raadily available forms and throw in a mesh half way in the pour.

 

[TDIengineer]

I agree with you Eric. Not worth saving 2" for a small area...

Just wondering if that wheel load was an impact load from being set down by a trash truck...