In Singapore, jacked piles are particularly advantageous in with nearby structures and sensitive residents. The jacked piling system uses dead weights to exert hydraulic pressure to push piles into the ground, producing less noise and vibration compared to driven piles, making it suitable for projects in urban areas where residents are sensitive to noise and vibrations.
The QP must maintain the following essential site and test records and keep them on site at all times:
Limit the maximum jacking force to 40% of the pile’s characteristic concrete cube strength ( 0.4fcu0.4 f sub c u end-sub
) is typically related to the ultimate geotechnical capacity ( cap P sub u ), often set at 2.0 to 2.5 times the working load (WL) Set Criterion:
Piling work must be supervised by competent and suitably qualified persons with comparable experience, as required by BS EN 12699. The site supervisor’s responsibilities include: In Singapore, jacked piles are particularly advantageous in
Under Eurocode 7 (EC7), which Singapore has adopted, design has shifted from prescriptive safety factors to a statistical, reliability-based approach. Site investigation data must be used to determine of ground properties—a process that requires professional judgement and statistical analysis. All soil tests must be carried out by a laboratory accredited under the Singapore Laboratory Accreditation Scheme (SAC-SINGLAS).
Operators must log the jacking pressure at every 0.5-meter to 1-meter interval. Sudden drops in pressure may indicate pile breakage or soft soil strata, while sudden spikes indicate boulders or hard strata refusal. Splicing and Joint Integrity
It is imperative to conduct an adequate site investigation to identify all ground formations and layers, and to determine ground properties. The extent must include a sufficient number of site investigation boreholes and sufficient exploration depth. Unnecessary cutting down in site investigation costs may prove to be “penny wise, pound foolish”—a cost too hefty to pay.
: If a pile penetrates a consolidating soft soil layer, designers must account for "downdrag" forces. This reversal of force (from positive to negative skin friction) must be considered when determining the required jacking load ( Pjcap P sub j Operators must log the jacking pressure at every 0
To guarantee execution safety, the Singapore Accreditation Council (SAC) sets forth strict criteria under standard for Specialist Builders in piling works. Operational personnel, including Piling Engineers and Supervisors, must maintain active listing in the IES/GeoSS Piling Personnel Registry as Certified Piling Personnel (CPP).
Project parties must submit in a timely manner the following documents in the issued by the Commissioner of Building Control together with the Notice of Approval for the first piling plan:
The guide specifies requirements for the jack-in rig to ensure stability and accuracy:
Advanced pile instrumentation techniques enable engineers to monitor pile performance during load tests. The has been introduced for driven, jacked‑in and bored cast‑in‑place piles load tests in Malaysia, Singapore and Thailand. This method enables installation of instrumentation after pile installation, virtually eliminating the risk of instrument damage during pile production and installation. The post‑install nature of the method enables engineers to select instrumentation levels along the as‑built depth of piles using pile installation records and site investigation data as guides. It reliably measures segmental shortening and strains over an entire section of the test pile during each loading step of a typical static load test, integrating individual measurements over a larger and more representative sample than conventional strain gauges. The has been introduced for driven
A pile is terminated when it reaches the design depth and sustains the required termination pressure—typically 2.0 to 2.5 times the working load—for a specified hold period (e.g., three cycles of 5-minute holds) without exceeding permissible settlement limits. 4. Quality Control, Risk Management, and Mitigations Risk / Challenge Potential Impact GEOSS Mitigated Best Practice
According to the GeoSS Guideline on Jacked Piles , several critical practices must be observed during the installation phase:
Using temporary open trenches or earth-retaining walls to contain ground movement within the project boundary. isomer-user-content.by.gov.sg Operational Good Practices Platform Preparation:
┌──────────────────────────┐ │ Rig Setup & Leveling │ └─────────────┬────────────┘ │ ▼ ┌──────────────────────────┐ │ First Element Pitching │ └─────────────┬────────────┘ │ ▼ ┌──────────────────────────┐ │ Continuous Penetration │ └─────────────┬────────────┘ │ ▼ ┌──────────────────────────┐ │ Segment Joint Welding │ └─────────────┬────────────┘ │ ▼ ┌──────────────────────────┐ │ Final Termination Criteria│ └─────────────┬────────────┘ │ ▼ ┌──────────────────────────┐ │ Quality Assurance Testing│ └──────────────────────────┘ Step 1: Rig Setup and Alignment