PSI - Issue 81

Yaroslav Kovalchuk et al. / Procedia Structural Integrity 81 (2026) 170–176

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Table 1. Numerical stress data in the lower chord of the 80 00×580 mm truss under loading applied to the lower chord nodes Coordinates along the X axis, mm P1 80 kN P2 120 kN P3 160 kN P4 240 kN P5 320 kN P6 400 kN P7 480 kN P8 560 kN MPa -7000 0.01 0.19 0.28 0.37 0.55 0.73 0.91 1.09 -6721.49 1.25 14.02 20.43 26.84 39.67 52.49 65.31 78.14 -6649.87 2.36 21.58 31.19 40.8 60.01 79.23 98.45 117.70 -6116.71 2.09 20.27 29.37 38.46 56.64 74.83 93.02 111.20 -5503.98 2.06 21.51 31.24 40.96 60.41 79.86 99.31 118.80 -5155.19 1.54 21.71 31.79 41.88 62.05 82.22 102.4 122.60 -4875.33 1.84 31.08 45.71 60.33 89.58 118.80 148.10 177.30 -4509.28 2.44 28.41 41.39 54.38 80.35 106.30 132.30 158.30 -3936.34 2.84 28.80 41.79 54.77 80.74 106.70 132.70 158.60 -3411.14 2.30 28.30 41.30 54.30 80.31 106.30 132.30 158.30 -3108.75 1.39 24.31 35.77 47.24 70.16 93.09 116.00 138.90 -2663.13 1.86 21.72 31.65 41.58 61.44 81.30 101.20 121.00 -2137.93 2.22 20.92 30.28 39.63 58.34 77.04 95.75 114.50 -1692.31 1.84 19.60 28.48 37.36 55.12 72.88 90.64 108.40 -1350.13 2.36 21.71 31.38 41.05 60.40 79.75 99.10 118.40 -1178.62 0.68 12.20 17.97 23.75 35.29 46.83 58.37 69.92 -1000 0.01 0.18 0.26 0.34 0.51 0.68 0.84 1.01 Based on the analysis of the stress distribution, it was established that: 1. The maximum stresses occur in the middle part of the truss’s lower chord, specifically in the section from 2.10 m to 3.6 m, i.e., at the intermediate nodes of the truss. 2. The maximum stresses at the intermediate nodes of the truss reach 180 MPa under a total load of 560 kN, ensuring the structural strength according to allowable stress limits. The computer- simulated experiment provided the stress distribution along the upper chord of the 8000×580 mm trapezoidal truss under various loads applied to the lower chord nodes, as shown in Fig. 8. As with the lower chord, the upper chord exhibits variable stresses along its length. From a structural perspective, this creates challenges for ensuring the truss’s strength, since areas where maximum stresses are localized are prone to damage and failur e. This effect may be particularly pronounced under cyclic loading.

Fig. 8. Stress distribution along the upper chord of the 8000×580 mm trapezoidal truss under different levels of loading applied t o the lower chord nodes. The displacement diagram of the control points along the upper chord in the Y-axis (deflection) over the length of the truss is shown in Fig. 9.