A modified HYSY 229 barge was utilized for the loadout, transportation and launch operation of LW3–1 CEP jacket. The barge is modified from a conventional launch barge (225mx52.5mx13.5m) to a "T" shape floatover and launch barge with a beam width of 42m at bow and 65m at stern. In order to verify the calculated results in transportation motion responses with this "T" shape barge, a model test in a model basin was performed and the test results were compared with these calculated results from the transportation motion analysis. From these comparisons, noticeable differences were observed with considerable higher motion responses from these model test results. During the final jacket transportation, a motion monitoring system will be installed at the jacket to further verify the motion behavior of this modified barge.

Based on the same reasons, a motion and trajectory monitoring device will be installed on the jacket during the launch in order to confirm the basic launch characteristics of this modified "T" shape launch barge. These collected data from these monitoring systems under real operational environments should provide a reliable design basis for the use of this large "T" shape barge for future jacket installations.

Control upending process was selected as the based case for LW3–1 CEP jacket upend design because of the large base dimension. This large jacket base dimension also imposes a challenge to maintain a minimum bottom clearance during the upending steps under a maximum crane hookload of 2,000mt. Extensive on-bottom stability analysis were performed to unsure the safety of the on-bottom stability under installation design conditions.

LW3–1 CEP piled foundation is the largest one in the world with 4 – 108" dia. vertical skirt piles at each jacket corner. Each pile is 158 meters in length. The maximum dry weight of one pile is 755mt. A 126m stick-up length in initial self penetration makes the pile design a challenge one in stick-up analysis and in fatigue analysis including both pile driving fatigue analysis and in-place pile fatigue analysis.

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