Parking Lot Drive Design....

[PowerStroke79_PE]

We are adding a bus lane to a drive within a parking lot at our local college. I always like to analyze the work we do and try and learn from it on the design aspect and not just on the construction side of it. Below is a picture of the work being performed along with the specs given to us. My main question is: What Code to follow, or design method I should say, would best reflect what was designed for this project? I worked it out with the ACI 330R-01, specifically Chapter 2. Any thoughts is much appreciated.

Specs:

3500 psi Concrete

#5's Grade 60 Rebar @ 12" O.C.E.W.

Keyway Joint every 30' or Cedar

6" Curb & Gutter

1' t 2' Cut out to meet grade.

 

[MikeMcC215]

Use the state DOT roadway specs, might be overkill but at least it should last.

 

[PowerStroke79_PE]

Well im pretty confident its over kill actually. What i want to find is a tolerance and maximum limit per say. The owner im pretty sure got suggested the specs by engineers but i think they played it safe. But i will look at their design recommendation, and i suspect its going to be AASHTO based.

Traffic is a category B by the ACI 330r, only buses and passenger cars. No biggy really..... Speed is never over 5mph which is why im looking at parking lot specs and not road or street deaign.

Thanks for the reply

 

[ptatohed]

We are adding a bus lane to a drive within a parking lot at our local college. I always like to analyze the work we do and try and learn from it on the design aspect and not just on the construction side of it. Below is a picture of the work being performed along with the specs given to us. My main question is: What Code to follow, or design method I should say, would best reflect what was designed for this project? I worked it out with the ACI 330R-01, specifically Chapter 2. Any thoughts is much appreciated.

Specs:

3500 psi Concrete

#5's Grade 60 Rebar @ 12" O.C.E.W.

Keyway Joint every 30' or Cedar

6" Curb & Gutter

1' t 2' Cut out to meet grade.

ImageUploadedByTapatalk1370966508.252978.jpg

I hope I understand your question. You're observing a construction site of a bus bay at your college and you want to know what codes were used for the design? Do you mean the design for the rebar placement specifically? I don't think you'll find a code stating how the rebar for a bus bay must be placed. If this project was in the public R/W, then the design would be per the local City/County standard plans (where I work, the City Standard Plans for a bus bay/turn out is 8" PCC w/ #4 bars @ 24" OC, both directions, over 6" AB over 12" min compacted native). But, since this project is on-site, there won't be any codes (or standards) requiring a particular design. It is up to the design engineer. The design will be on the plans and/or specs. The bar size and spacing would likely be on the plans and the connections would be per the specs. Similarly, as for the C&G, the plans could show its own detail, they could reference a local standard plan (City, County, DOT), or they could reference another accepted set of standard plans (like SPPWC). Not sure if that helps or not.

 

[PowerStroke79_PE]

Ok basically its this.

Im a contractor (sub-contractor primarily).

We were hired to do the above drive (bus lane) with the above specs.

I believe its over designed and would like to analyze its capacity.

I couldnt lol!

I analyzed it as a parking lot because speed is never (ever) over 5mph.

Im just intrigued to know what load capacity a 6inch slab, #5s @ 12 " O.C.E.W., PROVIDES, i mean its got to have an ultimate strength,, yield point, etc. AASHTO gives guidelines based on studies done in the 50's but isnt that more like forensics engineering? Evaluate existing, laods applied, and tolerance based on damage created. Just saying... Obviously the three different methods work, im justlooking for a way to finalize an answer that is kip/ft and so on.

 

[MWC PE]

Ok basically its this.

Im a contractor (sub-contractor primarily).

We were hired to do the above drive (bus lane) with the above specs.

I believe its over designed and would like to analyze its capacity.

I couldnt lol!

I analyzed it as a parking lot because speed is never (ever) over 5mph.

Im just intrigued to know what load capacity a 6inch slab, #5s @ 12 " O.C.E.W., PROVIDES, i mean its got to have an ultimate strength,, yield point, etc. AASHTO gives guidelines based on studies done in the 50's but isnt that more like forensics engineering? Evaluate existing, laods applied, and tolerance based on damage created. Just saying... Obviously the three different methods work, im justlooking for a way to finalize an answer that is kip/ft and so on.

As with anything I'm sure there is an ultimate load but pavement isn't really designed with that in mind, but rather designed for much smaller loads applied thousands of times daily for 20+ years. I would guess if you really wanted to know the ultimate load you could use ACI 318 and analyze it as a slab on grade.

 

[PowerStroke79_PE]

Thanks for the reply!