Open AccessMethodological approaches to assessing the stress-strain state of pipelines in cases of their asymmetric load on the sections of overhead crossings
Author(s) -
O. Yu. Korobkov,
Ye. Y. Ripetskyi,
R. Y. Ripetskyi
Publication year - 2021
Publication title -
rozvìdka ta rozrobka naftovih ì gazovih rodoviŝ
Language(s) - English
Resource type - Journals
eISSN - 2415-332X
pISSN - 1993-9973
DOI - 10.31471/1993-9973-2021-3(80)-36-45
Subject(s) - dimensionless quantity , curvature , geodetic datum , mathematical analysis , arc length , radius of curvature , mathematics , geometry , arc (geometry) , mechanics , physics , geology , geodesy , mean curvature , mean curvature flow
The geodetic surveys results of a number of above-ground pipeline crossings for various purposes in the study of stress-deformed state (SDS) are summarized. It is shown that pipelines are characterized by the process of asymmetric loading, which is manifested in the displacement of the maximum deflection arrow relative to the middle of the span. Methodical approaches to estimation of SDS of pipelines in cases of its asymmetric loading on sections of overpasses are offered. The minimum radius of curvature of the pipeline was chosen as the criterion for SDS assessment. In the first approximation, the curved axis of the pipeline is approximated by an arc of a circle and on the basis of geometric similarity the calculated formula of radius of curvature is obtained. The formula is extended to all cases of asymmetric loading by introducing the dimensionless function y(k) depending on the asymmetry coefficient k. This function y(k) is obtained using the theory of the curved axis of the beam, which is loaded by a concentrated force P, and approximated by a linear dependence. It is analyzed that at symmetrical loading the existing approaches to approximation of the axis of the pipeline by an arc of a circle give the underestimated result in an estimation of the SDS by 34%, and at asymmetric loading this discrepancy increases to 46%. The practical convergence of the results of the minimum radius of curvature with the experimental data is confirmed. The proposed technique is focused on the practical application of the processing of geodetic measurements, as it includes the parameters available for SDS control by geodetic instruments.