Imperfect upheaval subsea pipeline buckling

The objective of the research programme has been to develop a set of theoretical models suited to the perceived needs of industrial practice with regard to in-service, subsea pipeline buckling. The role of imperfections is shown to be of central importance. These factors are considered in the context of modern offshore engineering practice, including the particular employment of trenching and/or burial for purposes of protection. Novel, small scale, full thermo-mechanical system testing is presented, the design and construction of the actual experimental set-up being a key feature of the research programme. Subsidiary geotechnical experimentation is also undertaken. Theoretical studies employing the empirical data provided by latter are assessed against the resulting full system experimental data. With an introduction to the purpose of the research programme and the physical problem and its mechanical demands given in Chapter 1, Chapter 2 serves to clarify the factors involved. Although novelty involving the testing of burial pipe elements is present in the experimental studies of Chapter 3 the majority of original work lies in the theoretical studies of Chapters 4 to 6 and the full system experimentation reported in Chapter 7. The results of forty-five tests are therein provided and theoretical/experimental correlation considered. Definition of the upheaval state, crucial to offshore engineering requirements, is considered to be effectively provided for with regard to symmetric prototype configurations and a software suite of complementary models has been developed.