DESIGN AND ANALYSIS OF METALLIC RISERS. LIMIT STATE DESIGN

摘要

This paper gives an introduction to the main results from a 4 year Joint Industry Project (JIP) named "Design procedures and acceptance criteria for deep water risers" supported by international oil - and manufacturing companies. The ultimate outcome of the JIP is to develop a guideline for design and analysis of metallic risers. The guideline is intended to form the basis for a new DNV Offshore Standard OS-F201 "Design and Analysis of Metallic Risers" to be issued for industry hearing late 1999. The design format adopted is based on modern limit state design principles in a Load and Resistance Factor Design format with reliability-based calibration of partial safety factors. As an alternative, design checks formulated in terms of a simplified Working Stress Design format with calibrated usage factors also exist. The focus of the paper is on limit state design for Ultimate Limits States (ULS). The performance and benefit using the proposed LRFD and WSD formats will be discussed and compared to standard industry practice reflected by API RP 2RD.