Chapter 11 - Global buckling of pipelines

Abstract

Global buckling, also called ``beam buckling'', is the structural instability of the pipeline considered as a straight (or nearly straight) slender bar, subjected to compression, due to internal pressure and temperature. It is a different type of structural instability than local buckling (which is a ``shell buckling'' phenomenon) and refers to the classical ``Euler-type'' buckling of compressed bars or columns. The present chapter offers an introductory discussion of two main topics of pipeline global buckling: (a) upheaval buckling, and (b) lateral buckling. The two topics have several similarities, and they both refer to pipelines that exhibit significant compression during their operation, because of pressure and temperature. Controlling the shape of the buckle and the sequence of events associated with its formation and growth is essential for safeguarding pipeline integrity. In the first part of this chapter, the driving compressive force that causes global buckling in pipelines under pressure and temperature is presented. Then, the mechanism of upheaval buckling is examined, and a simple design approach is described, pinpointing the essential role of surrounding soil resistance. The last part of the chapter offers a brief presentation of lateral buckling in offshore pipelines and discusses several buckle initiation methods for mitigating the effects of buckles.