Determination of deflections of above-ground pipelines under loads in the longitudinal and transverse directions

¹ Tyumen Industrial University, 38 Volodarskogo Street, Tyumen, 625000, Russia
² The State Agrarian University of Northern Trans-Urals, 7, Respubliki Street, Tyumen, 625003, Russia

^* Corresponding author: cherentsovda@bk.ru

Abstract

The most common method of construction of field pipelines in permafrost-dominated areas is above-ground laying on supports. The size of the span between bearings is determined taking into account the condition of tuning out resonance frequencies in case of vortex excitation due to wind load. For these purposes it is necessary to determine the natural frequencies of vibrations of above-ground pipeline sections. When determining the natural frequencies of pipeline sections, it is necessary to take into account the initial position caused by additional loads in longitudinal and transverse directions (pre-stressed state of pipeline sections). A differential equation for determining the position of a pipeline section under stationary loads in longitudinal and transverse directions based on the rod theory is obtained. The numerical solution of the equation is obtained using the finite difference method. The influence of longitudinal and lateral forces is evaluated. It is shown that the influence of longitudinal and lateral loads has a significant effect on the initial position of pipeline sections. Therefore, the complex influence of loads should be taken into account for the correct determination of deflections. The initial position of the pipeline under the action of various combinations of loads can be used to evaluate the preliminary stress-strain state in the design of above-ground pipelines.