Heave monitoring of driven or jacked piles during installation is mandatory. This ensures that soil displacement does not cause adjacent piles to rise, which could lead to loss of capacity.
Inform the Qualified Person (QP) to review the soil profile and design capacity.
A pile is generally considered "set" if the downward movement does not exceed over a holding time of at least 30 seconds Re-jacking Procedure:
scribd.com/document/92651540/GEOSS-Guidelines-on-Good-Practices-for-Pile-Load-Test">Kentledge Method in Singapore? Heave monitoring of driven or jacked piles during
: Because jacked piles are displacement piles, they can cause "pile heave" in adjacent piles. Monitoring for heave is critical, and pro-active measures like pre-boring or relief wells should be used if necessary. Termination Criteria and "Set" Measurement
): The pile is jacked into the ground with a force adjusted in steps, usually reaching a value of .
By adhering to these GEOSS guidelines, developers and contractors in Singapore can ensure that jacked foundation piles are installed safely, efficiently, and in compliance with the highest engineering standards. A pile is generally considered "set" if the
The following practices are recommended by the GeoSS Guideline on Jacked Piles to ensure quality and safety during construction: :
In soft clay, use a refusal criteria of 125% WL at rest for 2 minutes, not peak jacking pressure, to avoid over-driving.
Conduct a Jackability Assessment using CPT data. Reject jacking if required force > 1.5 × static pile capacity (to avoid pile head damage). Termination Criteria and "Set" Measurement ): The pile
However, jacking piles is not simply "pushing steel into the ground." In Singapore’s complex geological profile—from Kallang Formation clays to Old Alluvium and even weathered sedimentary rocks—poor jacking practices lead to pile buckling, ground heave, and damage to adjacent structures. This is where the good practice guidelines become indispensable.
Maintained load tests are conducted on selected working piles to verify that settlement at design load and test load matches acceptable structural limits. Integrity Testing (PIT)
: Under no circumstances should the pile incline deviate by more than 1 in 75 from the true vertical position.
The Geotechnical Society of Singapore (GEOSS) establishes guidelines to ensure safety, quality, and efficiency in pile installation. This article outlines the GEOSS good practices for installing jacked foundation piles within Singapore's unique geological framework. 1. Understanding Jacked Foundation Piles