By V N Vijayvergiya, Fugro, A P Cheng, Amoco International Oil Company, and H J Kolk, Fugro Gulf
This paper was first published in GE’s March 1978 issue
Amoco International Oil Company has installed drilling and production platforms in Rough Field, in the British sector of the North Sea. The platform site is located about 30 miles (48km) east of Hull; an approximate location of the study area is shown in Fig. 1. Each platform has eight 36in (914mm) OD main pipe piles.
A quasi-effective stress method was used to compute capacity and design penetration of piles in chalk. Piles were driven to design penetrations which averaged 183ft (56.8m) for drilling platform and 130ft (39.6m) for production platform, using Menck 1500, 2500, 2500SL and 8000 hammers. Very long delays which occurred during pile driving were utilised to study the effect of soil-set on pile driveability.
This paper describes the procedures used in designing and installing the piles, analysis of soil resistance during pile driving and the effect of delay on pile driving.