Investigations Into Motion Responses of Float-over Barge by Scale Model Testing

Topsides installation by float-over method has received numerous attentions in offshore construction industry. This method uses an installation barge to install the topsides or production deck via ballasting and de-ballasting operations. Conventionally, for all these platforms, the topsides were lifted onto pre-installed jacket by using lifting installation method. The limitation in the capacity of heavy lifting crane barges in excess of topside weight have necessitated multiple lifting to be used, thus costing a huge amount of money. In addition, these heavy lift barges are unavailable for the platforms located in remote locations. This paper describes a series of float-over barge model tests subjected to regular and random waves. The objective of the paper is to investigate the responses of the barge in terms of motions during standby phase of the float-over installation. The experimental data are derived from model tests following Froude Scaling Laws with geometric scale ratio of 1:50. These consist of measurements of motions in six degrees of freedom to regular and random waves approaching barge model at wave heading of 180. The results provide useful insights and data into the actual seakeeping behavior of float-over barge.