1. GTL Helical (screw)
Piling
Oil & Gas Division
GTL Partner ship
Innovation below GroundTM – Foundation Solutions
2. Why use our solution in Oil & Gas?
• Speed of installation - typically a standard • Adaptable - Pile can be tailored to suit the • Program acceleration – If program
6m pile takes on average fifteen minutes to install. ground conditions from cohesive (clays) to requires acceleration then this can be achieved
This reduces contract program time, on site prelims, cohesionless (sands and gravels) soils or a quickly by deploying an additional power-head and
speed to market and plant closures amongst other combination of both. hydraulic unit. There is no waiting for additional
factors. materials or deliveries as this would already be on
• Reduced resource – a typical crew consists site.
• Sustainable and environmentally of three. An advantage on hazardous sites where
friendly – by reversing the installation process the mitigating risk is paramount. • Minimal Soil Disturbance – due to
helical pile can be decommissioned and re-used installation method unlike CFA or Rotary Bored.
leaving a Greenfield site. • Guaranteed product – quality control of Especially through sand and gravels
steel and fabrication gives confidence in the quality
• Reduced Environmental Impact - of the pile in the ground prior to installation. • Close proximity – to services, existing
Installation procedure produces minimal vibration foundations and buildings. No undermining.
and noise, allowing installation close to noise • End Bearing – the steel helix plate gives you
sensitive areas and night time operations. very good end bearing characteristics, with very little • Resistance to tension and
remoulding of the soil surface due to installation. compression – the pile can be used as a
• No spoil – with the spiraling cost of muck away tension anchor and soil nail.
the solution proves to be financially and • Flexible - Helix plates can be spaced to give
environmentally viable especially in contaminated particular failure conditions (end bearing or shaft). • Restricted access - Segmented sections
ground. for reduced head heights – piles can be installed
• Comparable - Monitoring of soils quality and under pipe racks.
• No Concrete - no curing time so loads can be capacity during installation, direct comparison to
applied immediately. A 60m mast foundation can be available site investigation and preliminary pile tests. • Cold temperature conditions - unlike
installed within one day. concrete that can only be installed above freezing
• Soil variability - Unforeseen variability in soils point without specialist equipement.
• Less disruption - Reduced deliveries unlike can be overcome by the addition of helical plates.
the wet trades, means less disruption to other on site • Low mobilisation/demobilistation
activities. • Quick test results - Preliminary Pile tests costs – equipment is delivered by a low loader
and results can be carried out and received with 48
• Up to 95% National Content – GTL train hours of starting test setup.
local labour under Supervision to install helical piles • Corrosion – within aggressive soils can be
accomadated
• On site Modifications - Variability in
• Workmanship – not so reliant on skill of rig penetration depth is achieved by additional pile
operator. Minimumal Instruments required to minitor sections. • No liners/casings – no requirement for
pile installation reducing errors and calibration. piling thorugh perched water tables or underground
water courses.
• Reinforcement cages – do not require full
• Waste – minimal materials wasted. Off site pre- length reinforcement cages and the problems
fabrication of piles and grillages reduces site waste associated
and disposal costs
3. 114mm Ø Helical pile with 350mm Ø plate penetrating 1200mm frost zone
Helical piles installed to North Platform and Grillage 7 awaiting top cap and heave
sleeve
4. Helical pile top cap with raking piles to accommodate high lateral loads
Steel foundation grillage fire protected
6. Final Helical pile section with heave sleeve
being installed under live pipe rack
National operatives ensure the pile
head is installed to datum under
GTL Supervision
7. North platform and pipe structure fire Grillage installed under pipe rack as
protected main header support.
8. To benefit from this solution please contact our
UK office
Tel: +44 (0)1403 741166
E-mail: info@gtl-partnership.com
Web: www.gtl-partnership.com
