The complete document, , can be downloaded from the GEOSS Civil Infrastructure Working Group website. An interactive verification tool is also available for registered geotechnical engineers.
Pile foundations are the unseen backbone of modern infrastructure, transferring building loads through weak soil layers to stronger strata below. While international codes provide robust frameworks for design, local practices often evolve independently, driven by the specific geological quirks of a region and the empirical experience of local contractors.
The guidelines provide strict procedures for applying load, monitoring settlement, and maintaining structural integrity during testing. The complete document, , can be downloaded from
Mandatory exploratory boreholes configured to specific grid intervals based on the structural footprint.
Local construction practices—such as driven precast piles, bored cast-in-situ piles, CFA piles, or screw piles—are evaluated against criteria like noise, vibration, ground heave, and spoil disposal. The guidelines verify which methods are proven to achieve integrity and capacity in each local soil type, including challenging conditions (e.g., high water table or dense layers). the Institution of Engineers Singapore (IES)
As stated in the 2016 circular: “Notwithstanding the requirements in this note, QPs must exercise their independent judgement and evaluation on whether more stringent requirements should be adopted especially where the ground conditions could be adverse or highly variable” .
Another local consideration addressed in GeoSS guidance is negative skin friction (downdrag) on piles—a particular concern in areas with soft compressible soils. Seminar materials from GeoSS identify common mistakes in designing piles subjected to negative skin friction, including: large kentledge setups can be massive
: The allowable concrete compressive stress for bored piles is restricted to 7.5 MPa under traditional working load conditions. Strict Settlement and Performance Limits
In Singapore, the kentledge method—using concrete blocks or steel plates as dead weight—is the conventional approach for determining geotechnical design values and pile response to applied load, both in settlement and ultimate load terms. However, large kentledge setups can be massive, reaching heights that pose safety hazards to workers and the public if improperly designed.
Guidelines provide verified recommendations for unit shaft resistance and unit base resistance tailored to local soil conditions.
In the context of geotechnical engineering, GEOSS refers to the , a professional body that plays a pivotal role in shaping deep foundation practices in Southeast Asia. The organisation works in close collaboration with government agencies such as the Building and Construction Authority (BCA), the Institution of Engineers Singapore (IES), and the Association of Consulting Engineers Singapore (ACES).