SCIA User Contest 2002

contraction during start-up and shutdown is also taken by the structure. The steel structure is designed as selfsupporting static system, which creates stable unit due to its dam walls and rigid beam grid on every platform level, able to transfer horizontal and vertical forces into foundations. The structure creates one independent expansion block. The steel structure is mostly open, with the exception of wall cladding between elevations +9,450 and +18,650, which is stiffened by auxiliary columns and cross-bracings. Protection wall is also made on elevation ±0,000 on three sides of the structure up to the height of +4,000 m. Main footprint dimensions of the structure are given by axes A, B, 1, and 2: 7,30 x 6,60 m. Auxiliary columns for supporting of extra platforms between elevations +9,450 and +18,650 are in the intersection of axes A, B, 1´, 2´ in the distance 3,450 m, resp. 2,450 from main axis 1, 2 Access to relevant platforms is enabled via side steel stairway. Stair beams are made of rolled steel beams, steps are made of galvanised gratings. Description of the Parts of STEEL STRUCTURE Columns are made of broad-flanged rolled beams HEB. There are erection joints on two elevations of the structure. Most loaded points are stiffened with transverse beams. Four anchoring bolts with T-heads anchor the structure into the foundations. Transversal beams are made of opensection rolled steel beams. The beams are partly supported or hanged into diagonal cross-bracings in the fields between columns. Parts are connected with bolts in the erection phase. The beams are secured against yawing with transversal beams in the pitch of 1 m max., the latter serving also as supports for galvanised grid covering of platforms. Diagonal cross bracings are made of pairs of open-section rolled steel beams. Connection to columns and beams is made through steel sheet flanges and bolts. Platform beams are made of system of rolled steel beams. Platforms are covered with hot dip galvanised gratings fixed to platform beams with fixing elements. The platform edges not protected with cladding walls are equipped with kick plates and railings. Two tracks for SCC access doors are fixed to platforms on elevations +15,150 a +28,920. Auxiliary stairs are made in the area of several platforms, thus connecting relevant platforms. The roof of cladded part of the structure is made of tear-drop steel sheets with thickness of 6 mm at the elevation of +18,650. The steel stairway is opened to the wind. Minimum width of the stairs is 800 mm and maximum slope is 45°. Stairs between relevant platforms are made of sloped steel U-shaped beams. Stair steps are made of galvanised gratings fixed with bolts. Resting platforms are equipped with kick plates and railings on the edges. Description of the method of Static calculation Static calculation is prepared with software IDA-PRIMA - integrated graphic computing system for static calculation by finite element analysis (FEA). It enables complex linear, non-linear, dynamic and stability design of any structure created by bars. Sizing of elements is in accordance with standards listed above. Deformations of the nodes The text enclosure C pages 1-50 (plastic index sheet No. 7) shows deformations of selected nodes in relevant load case combinations, the same in graphic enclosure F (plastic index sheet No.). The nodes were selected in all four corners on each platform elevation. Horizontal deformation in x, y direction should not exceed 1/500 of node elevation above support (of the structure as whole) acc. to recommended limit deformations in ENV 1993-1-1:1992, Eurocode 3. The software evaluates extreme deformations in every direction separately (x, y, z) as well as maximum node rotation around axes x, y, z. At the evaluation on page 52 it is shown, that the node with most extreme deformation is node No. 633 with deformation 55,8 mm in axis y. Since the nozzle is at the elevation of 28,920 m above the support, its deformation should be no more than 28920/500 = 57,9 mm, which is acceptable. Since the columns in the x-axis posses larger modules of inertia, the deformations are much smaller in this direction. Deformations of bars The text enclosure C page 53 (plastic index sheet No. 7) shows extreme deformations selected from all bars in steel structure, the same in graphic enclosure F (plastic index sheet No.). Since printed output for each bar will be extremely large, deformations of selected bars are also in graphic enclosure F (plastic index sheet No. 10) - mostly beams bearing the SCC. In this case, maximum deflection should be no more than 1/250 of beam length (about 26,5 mm) acc. to recommended limit deformations in ENV 19931-1:1992, Eurocode 3, which was met in each case. 81 SCIA User Contest Catalog

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