The paper describes a recent case of the abandonment and removal of an offshore platform in the Sea of Japan.
The Agaoki-kita platform which is sustained with twelve piles where the water depth is 90 meters, consists of a steel jacket structure which weighs approximately 6, 070 tons and a topside load of 3, 520 tons weight.
Firstly, the topside was cut and divided into seven pieces, and then they were transported by cargo barges to the shore for scrapping. Secondly, ten conductor pipes were cut by the explosives installed internally at 5 meters blow the seabed.
All eight main piles and four skirt piles were also severed by explosives resulting in the jacket being toppled down on the seabed. Finally, four large buoyancy tanks were attached to refloat the jacket in a horizonal position, and then it was towed about 10 kilometers and sunk down to the seabed for use as an artificial reef.
