Zawtika Pile Driveability

Gas Platform WP1 was installed in the ZTK-5, Block M9 site which is located approximately 290km west of Tavoy off the Myanmar coast. The platform consists of a braced steel jacket structure supported on eight open ended steel piles with two piles installed under each jacket leg. The piles had a diameter of 2.133m and were driven to a penetration depth of 120m below seabed. Significant difficulties were encountered during pile driving with the measured blow count exceeding the predicted values by the contractor. Further difficulties arose due to structural damage to the pile chaser which required remedial action to complete the pile installation.

In order to determine the root cause of these problems GDG was asked to investigate the accuracy of the original pile driveability analysis undertaken by the contractor. A key component of accurate pile driveability predictions is determining the static resistance to driving (SRD) which includes the resistance mobilised by the pile shaft at the soil-steel interface and the base resistance mobilised under the pile tip.

Scope of Work:

GDG was commissioned by PTTEP (Bangkok) to undertake a full third party design and checking exercise that involved extensive analysis of the jacket installation and piling operations.