×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Crushed Concrete Density?

Crushed Concrete Density?

Crushed Concrete Density?

(OP)
Just wondering if anyone has a good average density for crushed concrete pavement.  Our crusher makes it into 4-6" aggregate and I'm trying to convert cubic yards to tons.  Also, I have the same question about Recycled Asphalt Pavement..anyone have a density for that?  Thanks for any help.

RE: Crushed Concrete Density?

Hangontight....With pieces that large, your density will not be high...likely on the order of 90 to 100 pcf for the crushed concrete.

If it were crushed in the manner of a graded aggregate base material, the density would be upwards of 120+ pcf.

RAP will be somewhere in the 90 to 95 pcf range, depending on gradation.

RE: Crushed Concrete Density?

It varies some depending on the density of you local aggregates used to make the concrete, and on your percentage of voids. For the product you're talking about here in my area I'd figure about 110-115#/cubic foot.  

RE: Crushed Concrete Density?

you talking about densified in place or loose in back of haul truck?

i've seen heavier RAP (i want to say it ran about 125-130 pcf compacted but i'd have to double check since it's from a soil cement job i did a few years back)

RE: Crushed Concrete Density?

Sorry not much help here:

I have not seen any recycled concrete base that large used for roadway base. Largest has been 0-10% retained on the 1-3/4".

Also have not seen any RAP used as a base material. Did use an Iron Ore / RAP blend on a project (mostly I.O.) and the Da was around 135 pcf.

RE: Crushed Concrete Density?

i never used crushed concrete that big for pavements (other than stabilization of undercuts or a few feet below subgrade) but used rap in a soil cement design to cut the cement required versus using straight soil.

RE: Crushed Concrete Density?

I was asked to figure the piled density of some crushed concrete for a job I am working on. I recieved a sample and it is very clean and is about 2" to 3" pieces. I notice alot of brick mixed in. Using a pot of known density and lightly dumping the sample in the pot I ended up with a density of 82 PCF. Seems terribly low but with the 20% +/- brick does this sound possible? It has to be since it was actually measured out and tared here in the lab. What do you guys think?

RE: Crushed Concrete Density?

caddyyr2 -

You discovered the high variability of the density of larger particles. The weight/density of 82 pcf could be accurate for that sample.

Large (4" -6") pieces of concrete are generally cubical and angular.

The in-place density depends on the size and shape of the individual particles. Large pieces with no fines will give you a very low density (pcf) unless you have the optimum amount of fines of the correct gradation. - A one cubic meter of large spheres has a give weight. You can add a large amount of "marbles" in between the "grapefruit" and increase the weight of the cubic meter of materials without any compaction.

Cubic materials can be difficult to compact the solids because of the shape and friction. Physical vibration(compaction) does little to increase the density of large particles, while moisture and vibration can get much higher densities approaching 145 pcf.

RE: Crushed Concrete Density?

caddyr2....not out of range.  The dry rodded unit weight of coarse concrete aggregate will be in that range and slightly higher for normal specific gravity aggregate.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources