Critical upheaval buckling forces of imperfect pipelines

Prediction of the upheaval buckling critical force for imperfect submarine pipelines

“…Actually, those functions of initial imperfections adopted by Taylor and Tran (1993), Karampour et al (2013), and Zeng et al (2014) are all in this list.…”

“…(1) (Zeng et al, 2014) is a function which contains two independent parameters. It can be written as…”

“…The ends are fixed in both the X and Y directions. The downward force per unit applied on pipeline segment is modeled by identical and evenly distributed linear loads with its value 1500 N/m (Zeng et al, 2014). The change of temperature is 200°C which is used to model the axial loads caused by both change of temperature and internal pressure .…”

“…A new parameter is defined to express the differences of initial imperfection shapes. Finally, based on the works of previous researchers especially Zeng et al (2014) and Karampour et al (2013), a simple and united formula to calculate critical axial force is presented which covers both the effects of initial imperfection shape and the OOS. It can be used to predict the critical axial force for any known initial imperfection.…”

“…Taking into account the imperfection out-of-straightness as a whole, Zeng et al (2014) presented a new formula of critical force based on dimensional analysis. The formula is…”