FEATURES OF STRESS-STRAIN STATE CALCULATION FOR COMPLEX SYSTEMS OF OVERHEAD PIPELINE CROSSINGS
DOI:
https://doi.org/10.31471/2304-7399-2025-21(79)-280-294Keywords:
overhead crossing; multi-span pipeline; two-string system; stress-strain state; three-moment equation; bending moment; support reactions; deflection; pipe-line stiffness; initial parameters methodAbstract
The article is dedicated to the improvement of the methodology for calculating the stress-strain state of complex systems of overhead pipeline crossings, particularly two-string multi-span structures where pipelines are positioned one above the other. The relevance of the research is driven by the growing need for laying pipelines in mountainous areas and the necessity of utilizing existing support systems to reduce construction costs. It is shown that traditional approaches, based on simplified assumptions regarding the equality of bending moments in spans and at supports, do not reflect the actual operating conditions of the crossings and can significantly underestimate maximum stresses, especially in the edge sections.
The paper develops a detailed methodology that involves the stepwise determination of pipeline geometric parameters and loads from self-weight, product, snow, ice, and wind effects. The stress-strain state of the upper and lower strings is calculated based on the three-moment equation, followed by the determination of support reactions and the construction of bending moment and shear force diagrams. For the lower pipeline, the additional influence from the upper string is taken into account, which is modeled through applied forces equivalent to the support reactions.
Special attention is paid to determining deflections: for complex statically indeterminate systems, the initial parameters method is applied, which ensures high accuracy in calculating displacements at any point of the beam. The proposed methodology allows for obtaining reliable values for forces and displacements, which is essential for verifying the strength and stiffness of overhead crossings and ensuring their reliable operation in difficult terrain conditions.
References
1. Дорошенко Я. В. Спорудження магістральних трубопроводів: підручник. – Івано-Франківськ: ІФНТУНГ, 2009. – 517 с.
2. Orynyak V., Lokhman V., Sydor D., Radchenko S.A., Borodiia M.V. Analysis of the stress-strain state of an air crossing of pipeline in the course of repair // Strength of Materials. 2009. Vol. 41, No. 5. P. 581-591. https://doi.org/10.1007/s11223-009-9149-9.
3. Velychkovych A., Andrusyak A.V., Pryhorovska T., Ropyak L. Analyti-cal model of oil pipeline over ground transitions, laid in mountain areas // Oil&Gas Science and Technology – Revued’IFP Energies nouvelles. 2019. Vol. 74, No. 2. https://doi.org/10.2516/ogst/2019039.
4. Білобран Б. С., Дзюбик А. Р., Яновський С. Р. Вплив монтажного пружного згину на напружено-деформований стан надземних переходів магістральних нафтопроводів у горах // Нафтогазова галузь України. – 2013. – № 4. – С. 30–33.
5. Гайдаш, Л. М. Удосконалення відомого методу розрахунку оптимальної довжини консолей балкових переходів газонафтопроводів через перешкоди / Л. М. Гайдаш // Науковий вісник Івано-Франківського національного технічного університету нафти і газу. – 2011. – № 3. – С. 21-23.
6. Yeo IC, Roh M, Chun DH, Jang SH, Heo JW. Optimal arrangement design of pipelines up port by considering safety and production cost. International Journal of Naval Architecture and Ocean Engineering 2023; 15: 100531, https://doi.org/10.1016/j.ijnaoe.2023.100531.
7. Avrithi K., Kim H. Optimization of Piping Supports and Supporting Structure // Journal of Pressure Vessel Technology, Transactions of the ASME. 2017. Vol. 139, No. 4. https://doi.org/10.1115/1.4036144.
8. Писаренко Г. С. Опір матеріалів: підручник / Г. С. Писаренко, О. Л. Квітка, Е. С. Уманський; за ред. Г. С. Писаренка; 2-ге вид., допов. і переробл. – К.: Вища школа, 2004. – 655 с. – ISBN 966-642-056-2.
