Geoss Good Practice For Installation Of Jacked Foundation Piles In Singapore [2021] -

Good Practice Report: Installation of Jacked Foundation Piles in Singapore

1. Introduction

Jacked piling (also known as displacement piling) involves installing pre-cast concrete or steel piles into the ground using hydraulic jacks reacting against the weight of the rig or previously installed piles. In Singapore, jacked piles are widely used for:

Short Piles: If termination criteria are met but the pile is significantly shorter than the design depth, the designer must assess if the shallower depth is acceptable. 4. Quality Control and Safety Regulatory compliance and approvals

5.3 Pre-Boring and Assisted Jacking (where needed) than the approved plan, the designer must submit

Adjacent Structures: To protect sensitive nearby buildings from ground movement caused by displacement piles, practitioners may use: Relief wells or pre-boring at the pile point. Open trenches or temporary earth-retaining walls. Apply final 10 mm stroke

GEOSS requirement: Any pile failing PIT or SLT must be investigated by the QP, and a remedial plan (e.g., additional piles, under-reaming) approved before proceeding.

  1. Regulatory compliance and approvals

than the approved plan, the designer must submit an amendment plan and may require additional load tests to verify capacity. Protective Measures for Adjacent Structures

Step 6: Achieving Set & Termination

  • Apply final 10 mm stroke; record peak jacking pressure.
  • Hold pressure for 30 seconds. If no further penetration, set is achieved.
  • If pile creeps > 2 mm in that 30 seconds, continue jacking in 50 mm strokes until stable.

The following practices are recommended by the GeoSS Guideline on Jacked Piles to ensure quality and safety during construction: Verticality and Alignment: