Geoss Good Practice For Installation Of Jacked Foundation Piles In Singapore Link -

The Geotechnical Society of Singapore (GeoSS) provides guidelines for jacked foundation pile installation, emphasizing stringent controls on verticality, equipment calibration, and sequence to manage ground movement. Installation requires a re-jack process to reach specific settlement "set" criteria, typically 10mm or less, to ensure structural integrity. For the full guide, visit GeoSS.

Machine Capacity: It is recommended that jacking machines operate at roughly 75% of their maximum capacity to maintain efficiency and safety.

: Jack until refusal, release the force to zero, and re-apply without pause. This measures the downward movement, known as the "set". Standard Acceptance Machine Capacity : It is recommended that jacking

The Geotechnical Society of Singapore (GeoSS) draft guideline for the installation of jacked piles includes several "good practices" to ensure quality and compliance with Eurocode 7. Key Good Practices for Jacked Pile Installation

Before commencing installation, the following checks should be performed: 2 m/min (reduce rate

Settlement Limits: Allowable pile top settlements are typically limited to 15mm at 1.5 times WL and 25mm at 2.0 times WL.

5. Jacking Execution & GEOSS Controls

| Parameter | Good Practice Limit | GEOSS Trigger (Action Required) | |-----------|--------------------|----------------------------------| | Jacking rate | 0.5 – 1.5 m/min | >2 m/min (reduce rate, check hydraulic oil temp) | | Max jacking force | ≤ 80% of pile structural capacity | >85% – stop jacking, assess toe damage | | Heave of adjacent ground | < 10 mm | 10–25 mm – reduce jacking rate; >25 mm – stop, grout relief holes | | Pile verticality | < 0.5% deviation | >1% – de-jack, re-align; >2% – abandon pile | | Hydraulic pressure spike | < 15% of steady pressure | >15% – inspect pile head & shoe | 85% – stop jacking

The document Guideline on Jacked piles Draft Issue 20151031.pdf outlines technical procedures and "set" criteria for successful installation. Key installation practices mentioned include: Jacking Force ( Pjcap P sub j