Mechanical Behavior of Buried Pipeline Crossing Thaw Settlement Zone

Abstract

Thaw settlement is one of main reasons caused pipeline failure crossing cold region. The modeling method of mechanical response of pipeline crossing thaw settlement zone is proposed, the mechanical behavior of buried pipeline is investigated. Effects of pipeline and soil parameters on the buried pipeline were discussed. The results show that the high stress area and the maximum axial strain of the pipeline are at the edge of the thaw settlement zone. The upper surface of the pipeline is tensile strain while the lower surface is compressive strain. The maximum ovality of pipeline near the edge of thaw settlement zone tends to oval. The pipeline axial strain, ovality, and displacement decrease with the increasing of pipeline wall thickness while the change of high stress area is not obvious. The high stress area and ovality decrease with the increasing of pipeline diameter while the high stress area is expanded along the axial direction, but axial strain decreases slightly. The high stress area, axial strain, ovality, and displacement of pipeline decrease with the buried depth increases. With the internal pressure increases, the stress and axial strain of pipeline increase, but the ovality decreases. The soil's elasticity modulus has no obvious effect on pipelinès stress, axial strain, and displacement, but it can affect ovality slightly.