PROBLEMS OF SUPPORTING STRUCTURES OVERPASSES SECTIONS OF OIL AND GAZ PIPELINES OF LONG-TERM OPERATION

Abstract

Purpose. Generalizations of long-term surveys of the ground nodes of the overpasses sections of main pipelines (MP) which revealed on the basis of long-term surveys. Development of recommendations for minimizing the influence of detected deviations and damages of the elements of the supporting units on the further trouble-free operation of the overpasses sections of the main pipelines. Methodology. To achieve this goal, work was carried out in the following areas: development of recommendations and methods for performing repair and restoration of reinforced concrete structures; development of recommendations for providing the required load-bearing capacity of reinforced concrete piles and the method of installing the supporting rollers in the design position by means of a mobile lifting device without stopping the transportation of the product in the main pipelines. Results. On the basis of the conducted researches defects in supporting reinforced concrete structures, reduction of bearing capacity of piles and deviation of elements of support units from the design position and corrosion damages of sections of the pipeline under half-clutches were revealed. The modeling of stress-strain state (SSS) of MP overpasses sections is carried out on the condition that the pipe is at the same time an element of the building construction, which is subjected to vertical and horizontal loads: of its own weight, changes in temperature, wind loads and of technological element that is exposed to internal pressure. The loads acting on the overpasses section of the pipeline during the repair and restoration work were taken in the most disadvantageous combinations of factors that are inherent in the process of construction and operation of the MP. The determination of the SSS of the overpasses sections pipeline crossings was carried out on the basis of the finite element method. The magnitude of the stress state of the overpasses sections of MP was determined experimentally by electromagnetic method, using the device MESTR-411. Originality. Numerous studies of the state of elements of supporting reinforced concrete structures and moving construction with supporting rollers have been generalized. Methods of repair and restoration with the help of a mobile device without stopping the transportation of the product in the main pipelines have been developed. Practical value. The results of this study can be used in the planning of inspections and repairworks of main pipelines in operation. The developed method of repair and restoration allows to carry out repair in difficult places (river beds and floodplains, wetlands, etc.) without the use of heaving lifting equipment (cranes, pipelayers, etc.). Technological instruction for lifting main gas pipelines on supports of the overpasses sections during repair works was created.