Stress concentration factor (SCF) test results of large-scale tubular K-joints

Abstract

The chapter discusses the stress concentration factor (SCF) test results of large-scale tubular K-joints. The most commonly used method to estimate the service life of a tubular K-joint in offshore engineering is to refer to an S-N curve. When a tubular K-joint is subjected to certain loads, the hot-spot stress (HSS) range can be obtained by either numerical method or experimental test. From this S-N curve, the number of cycles can be predicted according to the corresponding HSS range. Thereafter, the life of a tubular K-joint can be estimated accordingly. The HSS range can be calculated from a parameter called SCF. The chapter carries out static tests on two large-scale tubular K-joints subjected under different loading cases. The HSS distributions along the weld toe for the two specimens are measured in the tests. Thereafter, the SCFs of the two specimens are obtained under different loading cases.