CE-801 (GS) - DESIGN OF STEEL STRUCTURES

Instructions:

  1. Attempt any five questions.
  2. Abbreviations have usual meaning.
  3. Mention the assumed data clearly.
  4. Use of IS 800-2007 and steel table is allowed.
  5. In case of any doubt or dispute, the English version question should be treated as final.

Questions:

  1. a) Design a laterally supported beam of effective span 6m for the following data: Grade of steel - Fe410 Maximum bending moment M=150kNm Maximum shear force V=210kN Check for deflection is not required. b) Design a welded simply supported plate girder for a span of 30m. The girder is loaded with uniformly distributed load of the intensity 35kN/m due to dead and live loads.
  2. Calculate the strength of a 20mm diameter bolt of grade 4.6 for the following cases. The main plates to be jointed are 12mm thick. a) Lap joint b) Single cover butt joint, cover plate being 10mm thick.
  3. Design a double angle discontinuous strut to carry a factored load of 135 kN. The length of strut is 3m between intersections. The two angles are placed back-to-back (with long legs are connected) and are tack bolted. Use steel grade Fe 410. a) Angles are placed on opposite side of 12 mm gusset plate. b) Angles are placed on same side of 12 mm gusset plate
  4. a) Design a seat connection for the factored beam end reaction of 110 kN. The beam section is ISMB 250 @ 365.9 N/m connected to the flange of column section ISHB200 @ 365.9 N/m using bolted connection. Steel is of Fe410 and bolts are of grade 4.6. b) What do you understand laterally restrained beams? Explain with diagram?
  5. a) Design an I section purlin for an industrial building, located at Chennai, with Galvanised iron sheets as the roofing material. Span of the truss =13m Spacing of trusses =6m~c/c Spacing of purlins =1.2m~c/c Wind pressure intensity =2~kN/m^{2} Weight of GI sheets =130N/m^{2} Grade of steel: Fe 410 b) Sketch and briefly explain any three failure patterns of bolted connection.
  6. a) Differentiate between bearing type connection and friction type connection. b) A tie member consisting of an angle section ISA~100\times75\times8, designed to transfer a factored axial load of 280kN, is to be welded to a gusset plate of 10 mm thick, using 6 mm fillet weld. Design the weld, if the weld is provided on three sides by overlapping the angle on the gusset plate, at a shop. Also sketch the connection showing the weld lengths.
  7. a) Write a note on grouping of timber based on modulus of elasticity and extreme fiber stress as per IS 883: 1994. b) An ISLB 300 carrying UDL of 50~kN/m has effective span of 8 m. This is to be connected to the web of girder ISMB 450. Design the framed connection using 20 mm black bolts.
  8. Write a short note on: i) Types of roof trusses ii) Purlins iii) Profile of gantry girder section iv) Deflection limits of gantry girders

End of Questions