×
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

Grout 28day break vs 7day met spec
4

Grout 28day break vs 7day met spec

Grout 28day break vs 7day met spec

(OP)
Client ordered 3000 psi Grout. Project requires 2000 psi.  Contractor wants to know if we still have to break the 28 day break eventhough at 7 days exceeds the 2000 psi spec.

What are the unseen potentials with not breaking the 28 day grout samples?

RE: Grout 28day break vs 7day met spec

2
You should probably make the 28 day breaks for a number of reasons -

1. The structural engineer should know the sample breaks at 28 days as a measure of the material in the project at the specified times. If this is grout for masonry, there are situations where high grout strengths are not desired and may be misleading/detrimental since the structural may often act differently. - As an example, if a grouted prism was made, you could get a false indication of the masonry strength of the outer fibers.

2. The supplier may appreciate the information for future reference regarding 7 v. 28 days strengths - if he is entitled to the reports. He should know the 7 day v. 28 day breal relationships of his materials.

3. The 28 day breaks could be very helpful in the case of a later problem and the question of accuracy and sampling comes up. You have a complete file where bad sampling, sample preparation, mishandling of samples or equipment problems could be pointed out.

4. You may also want the information for any future reference.

Dick

 

RE: Grout 28day break vs 7day met spec

I agree, break the 28 day samples.  No one may care about the results, but you can bet that if there is a future problem everyone will want to know what the 28 day break was.

RE: Grout 28day break vs 7day met spec

  From a contractual point of view, if the acceptance criteria is the 28 day strength, it matters not what the 7 day strength is for only the 28 day strength can "judge" the mortar (or concrete).  
  What I have had before is that both a 7 day and a 28 day strength were specified and we had low 7 days and okay 28 days or vice versa - the clause was an "and" clause meaning the mortar was in non-compliance if both the 7 and 28 day strengths were not met.

RE: Grout 28day break vs 7day met spec

(OP)
Thank you guys for your feedback.  My decision was to have the 28 day breaks.  And, as I said numerous times nobody is concerned until a nonconformance is evident.


Thanks,

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