QP National Security Shield Project

Scope of Work

G-Octopus performed the Pile Driving Monitoring during the installation of seven four-legged jackets. Monitoring included all driven sections of all foundation piles. The installation was carried out from the HLS 2000 Heavy Lift Vessel (NPCC) from June to September 2014, offshore Qatar.

The project represented pile driving in cemented rock layers for which refusal and pile damage criteria along with remedial action instructions had to be assessed. The service included the real-time monitoring and interpretation of pile tip damage and axial capacity and evaluating the set-up factor and long-term axial pile capacity based on restrike tests.

All pile sections were prepared for monitoring and instrumented offshore, on-board cargo barges. Piles were driven safely to the target penetration. Expected axial pile capacities were demonstrated for the acceptance of the all foundation piles.

Following documents were issued for the project:

• Technical specifications for driving refusal and pile damage criteria
• Long term capacity assessment specifications
• Pile instrumentation and Offshore operations Method statement
• Operational procedure
• Filed Report, and Acquired Data
• Final Report, interpreted data and Signal Matching Analyses results.

Services Included:

• Pile Driving Monitoring and Dynamic Load testing of each section of  each foundation piles of 7 jackets.
• On-board advice and safe driving criteria to prevent pile tip buckling in hard soil conditions and for remediation of premature refusal.
• Analysis of Pile Driving Monitoring data, assessment of ultimate pile bearing capacity.

Pile Info

Open ended steel piles
Length: 87 to 153 m
Thickness: 32 to 50 mm
Diameter: 1.067 to 1.219 m

Equipment Used

Brand: PDI
Type: PDA-PAX
Sensors Type: Standard
Number of sensors: 2 Strain transducers, 2 PR accelerometers