PROJECT QUALITY CONTROL AND PILE TESTING

STATIC LOAD TESTING

A static load test (SLT) is the most reliable method of determining pile load capacity. It is the most fundamental pile test type for determining its load capacity and is considered the benchmark of pile performance. It involves the direct measurement of pile head displacement in response to a physically applied test load. Testing a pile to failure provides valuable information to the design engineer and is recommended for load pile tests performed prior to the foundation design or working piles construction.

This method is applicable to all types of piles regardless of their method of installation. Piles can be tested for:

  • Compression
  • Lateral
  • Tension (i.e. uplift)

For the SLT the load is most commonly applied via a jack acting against a reaction beam, which is restrained by an anchorage system or by jacking up against a reaction mass (“Kentledge” or dead weight.)

The anchorage system or crown system is usually in the form of Tieback Anchors installed into the ground to provide tension resistance. The nominated test load is usually applied in a series of increments in accordance with the appropriate code, or with a pre-determined load testing specification for a project. Each load increment is sustained for a specified time period, or until the rate of pile movement is less than a nominated value. Static load testing methods are applicable to all pile types, on land or over water, and may be carried out on either production piles or sacrificial trail piles.

pile testing

Additional to static Load Testing ( SLT), Other pile testings are required and mandatory by local authorities to ensure the integrity and the capability of the piles to carry the design loads. Such pile testings are usually carried out by a third party licensed and approved by local authorities. Pile test reports are the key tools for each type of test which shall include in detail the method of conducting the test, equipment used data, and results which come in the form of values or graphs whatsoever. The most common tests are but are not limited to:

  • High strain dynamic test
  • Low strain integrity testing known as ( Pulse Echo Test)
  • Cross-hole sonic logging
  • Caliper logging