PSI - Issue 81

Artem Bilyk et al. / Procedia Structural Integrity 81 (2026) 177–183

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4. When manufacturing from one sheet, one type of product is made, that is, only flange or only a wall. The wall and flanges are cut from different sheets. The problem of optimal cutting of different products from one sheet is not currently considered. With a large number of beams of the same type, this assumption is quite acceptable. Available sheet workpieces are determined by the capacity of metallurgical plants. The analysis took into account the current positions of sheet metal of key domestic metal traders according to the data presented by Ukrainian Steel Construction Association, Table 1.

Table 1. Current positions of rolled steel sheets for the manufacture of beams Thickness, mm Size, mm

Hot-rolled sheet 5.0 Hot-rolled sheet 6.0 Hot-rolled sheet 8.0 Hot-rolled sheet 16.0 Hot-rolled sheet 20.0 Hot-rolled sheet 25.0 Hot-rolled sheet 30.0 Hot-rolled sheet 40.0

1500х6000 1500х6000

1500х6000 2000х6000 1500х6000, 2000х6000 1500х6000 2000х6000 1500х6000 2000х6000 1500х6000 2000х6000 1500х6000 2000х6000

Hot-rolled sheet 10.0; 12.0; 14.0

2000х6000

As can be seen from Table 1, the main width of the workpieces is 1500 and 2000 mm. 2) Technological limitations of MS plants regarding sheet dissolution.

In 2021, together with the Ukrainian Steel Construction Association, a special questionnaire for steelworks was developed. The results were provided by major steel structure manufacturers. The questionnaire data have been processed and are presented in Table 2.

Table 2. Technological limitations of MS plants in Ukraine regarding sheet cutting and accepted values Parameter Value Standard trimming width 5-10 mm, accepted 10 mm Cutting width depending on sheet thickness Sheet thickness, mm Cutting width, mm 1-6 1.7 8-12 2 14-30 2.5 32-60 3 62-100 4

Thus, we obtain a table of all possible combinations of sheets for workpiece widths of 1500 mm and 2000 mm. «Division number» - this is an integer into which the sheet is divided by width, taking into account technological limitations. Using Division numbers from 1 to 14 we get the volume Q=302 sheet cutting options with the thickness 5-40 mm, the width of the workpiece 1500,2000 mm and different sheet width 101-1480 mm. Longitudinal welded joints (if any) must be of equal strength according to regulatory requirements and do not affect the choice of the optimal beam cross-section. These sheets form the FRS, from which the wall or beam flanges can be selected. 3) Technological limitations of metal structures (MS) plants regarding the formation of welded I-beams. Let us consider the technological variable limitations associated with the manufacture of welded beams. They are systematically listed in Table 3.

Table 3. Technological limitations of MS plants in Ukraine for the production of beams and accepted values Parameter Minimum value, mm Maximum value, mm Wall height h w 180..200. For beams we take no less than 200, h w ≥ 200 1200…1500. Accepted h w ≤ 1500 (acceptable for most factories) Wall thickness t w 4..5. Accepted t w ≥ 5 due to product range limitations 40…50. Accepted 40 (acceptable for most factories) Flange width b f 100. The limitation on the ratio of flange width to wall height is related to the convenience of performing welds b f ≤ 1,55h w 600…1000. Accepted b f ≤ 600 (acceptable for most factories)

Flange thickness t f

5…6 mm. Accepted t f ≥ 5. Also accepted t f ≥ t w , t f ≤ 4ꞏt w

40…50. Accepted 40 (acceptable for most factories)

Another type of variable constraints are structural constraints based on regulatory cross-section checks. The main constraints according to DBN V.2.6-198 are: strength under normal stresses; tangential stress strength; deflection limits; checking the local stability of flanges and checking the local stability of the wall. It is worth emphasizing that I-beams are not selected based on inspections, but rather those options that do not pass them are eliminated – the FRS is reduced. If technological and production constraints are more constant, as they are generalized with respect to the capabilities of plants, then the constraints on regulatory checks depend directly on the conditions of the specific task of optimal cross-section selection. Therefore, as a result, after