SUBSEA PILEDRIVING: A BREAKTHROUGH.

In 1977 at two widely distant locations and at about the same time, piles were driven underwater to give subsea structures a reliable piled foundation into the seabed. These were the Cognac field in the Gulf of Mexico and the Pulay field in the South China Seal. In both cases a Hydroblok hammer was used, a large HBM-3000A hammer in the United States and a small HBM-500 type in Southeast Asia. Both operations have shown that underwater driving can be safely accomplished under real offshore conditions. Details of the two pile-driving operations and the type of equipment used are given.