Structural Safety Assessment of Existing Ice-Resistant Jacket Platforms in Ice Zone

Until now dozens of offshore structures have been deployed in Bohai bay since the first drilling platform was erected in 1965. The oil and natural gas resources of Bohai Bay are mainly marginal oil fields. It is necessary to build both ice-resistant and economical offshore platforms. Full-scale measurement for many years shows the design of some ice-resistant platforms is not so sophisticated, the most significant is that ice induced vibration is the main which has caused harmful accidents in Liaodong bay of Bohai. In order to ensure security operation, structural safety assessment and life extension become key problems. In this paper, failure modes of ice resist jacket platforms, the related failure evaluation criteria, and risk grade are treated. Combined with monitoring data of ice loads, assessment strategy is presented. Lastly, as an application example, safety assessments of a practical platform in Bohai Bay are carried on.Copyright © 2009 by ASME