Upheaval buckling (UHB) is the buckling of a pipeline due to upward movements of the pipeline. Ratcheting is the progressive (upward) movement of a pipeline due to cyclic loading, resulting in expansion and contraction of the pipeline. These two phenomena, UHB and ratcheting, are connected, but not the same. UHB and ratcheting mostly occur in long, almost straight pipelines, both offshore and onshore that undergo temperature fluctuations.