×
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

Proof-rolling.

Proof-rolling.

Proof-rolling.

(OP)
Proof-rolling has often been suggested as an alternate method for compaction testing. If the material lift is 8-12", near optimum moisture and the compaction effort ( weight / amplitude / pattern ) is adequate, what criteria should be used for interpretation, with respect to material type; crushed top courses, pit runs, clays / silts, etc ?
I'd appreciate your input.

RE: Proof-rolling.

Proofrolling to me has always been done with a purpose of
(1) identifying soft spots in the subgrade (of a road or building footprint with slab-on-grade) and
(2) ensuring a "uniform" density in the uppermost zone of the natural stratum.

It has never been done to obtain a specific degree of compaction.  I've seen this specified and have always wondered why it is so - if you aren't happy with the material at the founding level, you shouldn't have designed for it to be at that particular level.  

RE: Proof-rolling.

Looks like you two are using different definitions of "proof rolling."  Like Big H, I've always used the term to mean testing of the foundation before putting in embankment fill or a structure.  I would call what Sayler is talking about a "test fill." Pick the criterion you want to design for (e.g. 95% std., 70% RD), and experiment with what equipment, moisture, no. of passes, etc. you need to get that.  For coarse materials, you might not be able to measure densities without a huge water-filled ring test (analogous to a sand cone test) or come up with a really credible maximum density, so you experiment to see what you can get with typical equipment and procedures, and go with a procedure spec instead of a performance spec.  ("...shall be compacted by a minimum of four passes of a 10-ton vibratory roller, with lift thickness not to exceed 18 inches loose..." VS "...shall be compacted to achieve density equal to or greater than 95 percent...")

RE: Proof-rolling.

thread261-137601

try this for a little more info on how to conduct and quantify your proofrolling tests

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