This sort of load testing is performed on-site, live, on test piles you've built there. The design capacity of the pile is clearly indicated by this test. The test itself is straightforward ? put enough weight on the pile and see how much it flattens. Keep applying more load on the test pile incrementally and measure its settlement, seems simple enough.
You can jack up dead loads on the pile, or use beams to uplift anchor piles to supply reaction for the jack. You can either use the Constant Rate of Penetration (CRP) or Maintained Load (ML) test to gauge the settlement data.
When would you know that the pile has had enough and the load can't be considered safe anymore for that pile? Well, the engineering community is still divided about it. Terzaghi (1942) said if the pile settles by 10% of its own diameter, the load causing that is the failure load. However, the German DIN 4026 says when the pile has undergone irreversible settlement of at least 2.5% of its own dia, then that's the max load for that pile.
Published By
Arka Roy
www.constructioncost.co
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