Section B (refer to the datasheets when answering the questions in this section) B1 Figure B1 shows the end elevation of

[answerhappygod]

Section B Refer To The Datasheets When Answering The Questions In This Section B1 Figure B1 Shows The End Elevation Of 1 (62.05 KiB) Viewed 63 times

Section B Refer To The Datasheets When Answering The Questions In This Section B1 Figure B1 Shows The End Elevation Of 2 (59.8 KiB) Viewed 63 times

Section B (refer to the datasheets when answering the questions in this section) B1 Figure B1 shows the end elevation of a three storey rectilinear steel structure in simple construction. The structure is 20m long in the direction perpendicular to the plane. To resist wind load on the structure in the direction of the plane as indicated in Figure B1, bracing is required at each end of the structure. Two options of bracing are considered: (1) using cross-bracing (as indicated by the dotted lines in Figure B1); (2) using diagonal bracing (one of the cross-bracing members in each storey in Figure B1 is removed). The steel grade is S355. The characteristic wind load (variable action) is 0.4kN/m² (a) Calculate the maximum design load applied to the bracing [9 marks) (b) Flat plates are to be used in cross-bracing. Select a suitable plate size. One line of holes of 18mm diameter along the plate length will be drilled for connection [7 marks] (c) When using diagonal bracing, a hot-rolled circular tubular section of CHS 114.345 (diameter 114.3mm, thickness 5mm) will be used. The cross-sectional area and radius of gyration of the section are 1720mm² and 38.7mm respectively. Check whether this section is sufficient. 11=75.5. [9 marks) om K Wind direction cach story 4.5m Figure B1
B2 A 5 storey rectilinear steel framed structure in simple construction has 3 bays of 6m in the shorter direction and 6 bays of 9m in the longer direction. Columns are placed at bay junctions and support steel beams in two perpendicular directions which support floors. Each storey is 4.2m high. The characteristic permanent and variable actions on all floors are 4kN/m2 and 5.5kN/m2 respectively. The edge columns in the longer direction of the structure use UC section UC254x254x89 and the columns are orientated so that their flanges are parallel to the length of the structure. The steel grade is S355 and 1=75.5. (a) Sketch the floor plan layout of the steel frame structural arrangement. [2 marks] (b) For an edge column on the first floor, calculate the design loads in the column. This edge column supports reaction forces from beams in the two perpendicular directions and the reaction forces in the two directions are split 50/50. [10 marks) (c) Check section classification, e=0.814. [3 marks) (d) Check whether the proposed section is adequate under the calculated design loads. Xmin=0.553 [10 marks]