PSI - Issue 36

244 O. Fomin et al. / Procedia Structural Integrity 36 (2022) 239–246 Oleksij Fomin, Alyona Lovska, Volodymyr Bohomia et al. / Structural Integrity Procedia 00 (2021) 000 – 000 Goolak et al. (2020)). The number of nodes of the finite-element model was 235153, and the number of elements was 729323. In this case, the maximum size of the element was 40 mm, the minimum one – 8 mm. The number of elements in the circle was 9. The ratio of increasing the size of the element was 1.7. When compiling the calculation scheme, it is taken into account that the model is loaded with its own weight Рв. In the areas where the load-bearing structure of a tank wagon is supported by the trolleys, elastic elements for modelling the spring suspension of the latter were installed. Elastic elements were also installed between the pot and its supports on the frame (Fig. 4). Steel of grade 09Г2С was used as a construct ion material. The results of the calculation are shown in Fig. 5. It is established that the maximum accelerations of the load bearing structure of a tank wagon occur in the area of the manhole and are 2.8 m/s 2 .

Fig. 4. Calculation scheme of the load-bearing structure of a tank wagon

Fig. 5. Accelerations acting on the load-bearing structure of a tank wagon

In this case, the discrepancy between the results of computer and mathematical modelling was about 8%. The coefficient of fatigue resistance of the load-bearing structure of a tank wagon was also calculated in the study (DSTU 7598:2014, GOST 33211-2014, Ustich et al. (1999)):   . a, 1 n n е L =  −   (6) To determine the stresses in the load-bearing structure of a tank wagon with actual dimensions, a calculation was performed according to the scheme shown in Fig. 4. It is established that the maximum equivalent stresses in the load-bearing structure are about 165 MPa. The results of the calculation showed that the coefficient of fatigue resistance is equal to 2.6. At the same time, due to the lack of experimental data, the allowable value of the coefficient of fatigue resistance reserve is assumed to be 2.2. Therefore, condition (6) is fulfilled and the fatigue strength of the load-bearing structure of a tank wagon is provided. According to the calculation scheme shown in Fig. 4, the most loaded zones of the load-bearing structure of a tank wagon were also defined by means of options of the SolidWorks Simulation software complex (Fig. 6).