Pile capacity testing

: Abstract As there is still uncertainty in accurately predicting the performance of piled foundations based upon design calculations, there remains a need to test piles. Several methods of pile testing are available, some of which have been in common usage for many years, while others are relatively recent developments. Static pile testing is a well understood and simple test technique that has been in use for many years. This approach has the benefit of directly producing test results but is hindered by the increasing size of associated testing infrastructure as pile capacity increases. A recent variation of classic top-down static testing is bi-directional testing which relies on the incorporation of a specialised loading jack or jacks in the pile shaft at some depth below the ground surface. This technique has the ability to apply test loads that greatly exceed those possible in other pile test types by effectively using one portion of the pile capacity to test against the other or others. Alternative pile testing techniques come in the form of rapid and dynamic load tests that have the benefit of quick testing and reduced testing infrastructure, but require more complicated analysis and interpretation techniques due to the rapid/dynamic nature of the tests.