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


When to conduct pile load test

When to conduct pile load test

When to conduct pile load test


After pile driven into soil, when is the appropriate time to conduct the pile load test (maintained load test & pda test)

1. Is the resting period for skin friction and end bearing pile is different? I read that some suggesting straight away, some said 3 days, 2 weeks and even 1 month.

2. Will different type of soil affect the time for testing?

3. What about the bored pile?

Thank you

RE: When to conduct pile load test

General rule: for silts and clays, the longer the wait, the higher the static capacities (full-scale load test). For mostly sandy profiles, 1 to 2 days.
Practically, the sooner the better, so pile production can start.
For auger cast piles, we never waited more than 1 week.
If the contractor is pushing for a shorter wait time between installation and test, the test results will be conservative (everyone wins unless the test results are lower than expected).

RE: When to conduct pile load test

For PDA tests on large project we usually do some tests at the end of initial drive and some after a week or two to determine the amount of setup (or relaxation).

I have seen piles with fairly substantial relaxation so you should be cautious about assuming that the longer you wait the higher the capacity will be as this is not always true.

RE: When to conduct pile load test

My experience was minimum one week to allow the soil thixotropy, releasing the excess pore water pressure and soil dilatation.
The bored pile will be depending on the concrete strength to hold the maximum load.

RE: When to conduct pile load test

In what soil profiles do you see substantial relaxation beyond 7 days?
Is this demonstrated by full scale pile load tests, or just PDA, or both?

RE: When to conduct pile load test

Driving piles in very dense silty sand. The mechanism is supposedly negative pore water pressure generated during driving. Demonstrated by PDA tests in some cases, in others simple observation - the pile reaches practical refusal at the maximum allowable energy, but is able to be re-driven a day later.

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! Already a Member? Login


White Paper - The Criticality of the E/E Architecture
Modern vehicles are highly sophisticated systems incorporating electrical, electronic, software and mechanical components. Mechanical systems are giving way to advanced software and electronic devices, driving automakers to innovate and differentiate their vehicles via the electric and electronic (E/E) architecture. As the pace of change accelerates, automotive companies need to evolve their development processes to deliver and maximize the value of these architectures. Download Now
White Paper - Model Based Engineering for Wire Harness Manufacturing
Modern cars, trucks, and other vehicles feature an ever-increasing number of sophisticated electrical and electronic features, placing a larger burden on the wiring harness that enables these new features. As complexity rises, current harness manufacturing methods are struggling to keep pace due to manual data exchanges and the inability to capture tribal knowledge. A model-based wire harness manufacturing engineering flow automates data exchange and captures tribal knowledge through design rules to help harness manufacturers improve harness quality and boost efficiency. Download Now
White Paper - Modeling and Optimizing Wire Harness Costs for Variation Complexity
This paper will focus on the quantification of the complexity related costs in harness variations in order to model them, allowing automated algorithms to optimize for these costs. A number of real world examples will be provided as well. Since no two businesses are alike, it is the aim of this paper to provide the foundational knowledge and methodology so the reader can assess their own business to model how variation complexity costs affect their business. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close