For the development of requirements for loads to the test bench for pipes, an analysis of the bearing capacity of the pipeline was carried out with internal pressure, axial force, bending and torque acting in its cross section. Investigations were carried out to determine the effect of torque on the bearing capacity of the pipeline under combined loading and to determine the need for loading of pipe samples with torque during bench testing of pipes. For the analysis, a simple analytical dependence of the limiting bending moment on internal pressure, axial force and torque was obtained. As a design scheme of the pipeline adopted a beam of tubular section. A material model without hardening has been adopted. In this case, the presence of hoop stresses fr om internal pressure was taken into account. The calculation of such a beam under a biaxial stress state (with allowance for hoop stresses) reduces to the calculation of a conventional beam under a uniaxial stress state, the material of which has different yield stresses during compression and tension. The calculation was carried out in the software complex implementing the finite element method. The results of analytical calculations are compared with the results of numerical modeling of the bearing capacity of the pipeline by the finite element method. Satisfactory correspondence of the results of calculations is obtained. The effect of torque on the bearing capacity of the pipeline under combined loading of the pipeline is investigated. The results of the investigations made it possible to justify the insignificant influence of the torque on the bearing capacity of the pipeline under combined loading in the investigated range of load changes and to turn out from the load function of the pipe specimen as a torque during the development of a specialized test bench.
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