Reliability Assessment Model for Aging Jacket Structures in Malaysian Waters

As the world is progressing towards deeper water technology, jacket platform still remains as an important production structure for oil and gas in Malaysian shallow water regions. Besides the discovery of new oil and gas, enhanced oil recovery (EOR) allows more oil to be extracted from the old fields. As a result, service life of existing fixed jacket platforms need to be extended. The overall reliability of aged platform has to be reevaluated in order to monitor the integrity of the structure, and to prevent unexpected failures. Reserve Strength Ratio (RSR) is a widely adopted measure to quantify the ultimate strength of a structure. However, structural strength alone is inadequate to express a structure's reliability. Reliability is best defined as the probability that the extreme load will not exceed the ultimate strength of a structure. It can be expressed either in probability of failure or reliability index, which is the inverse normalized form of probability of failure. This paper presents the study of existing jacket platforms in Malaysia's three oil and gas operating regions. Relationship between probability of failure, reliability index and RSR has been formed to provide a simple reliability assessment model of jacket structure in Malaysia water regions.