2. Technical Engineering: The GeoSS Set and Termination Criteria
As building codes transition to the Eurocode framework, engineers must follow specific installation controls, verification criteria, and quality management frameworks to minimize ground movement and secure predictable pile capacities. Technical Overview of Jack-In Piling
By working together, the industry can ensure that jacked foundation piles are installed safely, efficiently, and to the required standard of quality, ultimately contributing to the development of a safe and resilient built environment in Singapore.
| | Key Requirements & Methodology | | :--- | :--- | | Design Compliance | Must adhere to Eurocode 7 and BS EN 12699 for the design and construction of displacement piles. | | Risk Management | A differentiated approach based on building risk category is mandatory. Higher-risk projects have stricter requirements. | | Heave & Settlement Control | Rigorous monitoring of pile heave during installation is essential, including heave of adjacent piles and ground settlement . | | Piling Plans | Must include additional information on the piling plan submitted to BCA for approval to enhance oversight. | | Approval & QC | Before any structural work above the piles (e.g., pile caps) can begin, a written confirmation must be obtained from the Commissioner of Building Control. | | Documentation | Requires mandatory submission of an "Interim Certificate of Supervision on Piling Works" at 50% and 100% pile completion, and a settlement monitoring certificate at every five-storey milestone. | | | Key Requirements & Methodology | |
Strict control of verticality is paramount. The pile should not have its alignment adjusted by force during installation. Forcing a pile into position can create excessive bending moments, leading to structural damage or reduced bearing capacity.
Because jacked piles are installed in segments, the splicing of sections is a critical failure point.
: If piles encounter boulders or hard intermediate layers, they may end up shorter than designed. Any reduction in length greater than | | Heave & Settlement Control | Rigorous
Unlike traditional driven piles that rely on dynamic impact hammers, jack-in piles utilize hydraulic rams to smoothly push precast concrete or steel elements directly into the soil matrix. Equipment and Machine Capacity
However, over the long term, that same consolidating soil exerts a downward drag force known as . Designers must account for this force reversal when sizing the targeted jacked load ( Pjcap P sub j ) during physical installation.
: The termination jacking force typically targets a value between 2.0 to 2.5 times the Working Load (WL). focusing on safety
It is recommended that the jacking machine be used at no more than 75% of its maximum capacity to ensure safety and equipment longevity.
: The pile must achieve the verified load capacity measured via calibrated hydraulic pressure.
The developed guidelines to standardize the installation of jacked foundation piles , focusing on safety, environmental benefits, and technical compliance with Eurocode 7 (EC7) . Core Installation & Termination Criteria
Unlike conventional driven piles, jacked piles benefit from a continuous installation process. The hydraulic system offers real-time readouts of the downward force being exerted. This operational transparency eliminates much of the guesswork associated with standard dynamic pile driving.
