CE-801 Design of Steel Structures - May 2023 Question Paper

Under each question, How to answer lists the points an answer should cover, outlined by CampusPrep from the syllabus. Check the details against your textbook.

1. 14 Marks
   Design a lap joint between the two plates each of width 120 mm, if the thickness of one plate is 16 mm and the other is 12 mm. The joint has to transfer a design load of 160 kN. The plates are of Fe 410 grade. Use bearing type bolts.
   How to answer

   • Determine bolt strength in shear and bearing for Fe 410 and bearing-type bolts per IS 800-2007.
   • Determine number of bolts required for 160 kN design load.
   • Check pitch, gauge, edge distances and plate tensile strength.
   • Give joint layout sketch with staggered/chain arrangement.
2. 14 Marks
   A tie member consists of two ISMC 250. The channels are connected on either side of a 12 mm thick gusset plate. Design the welded joint to develop the full strength of the tie. However, the overlap is to be limited to 400 mm.
   How to answer

   • Compute full tensile strength of two ISMC 250 as tie per IS 800-2007.
   • Determine required weld strength and size for full strength development.
   • Check overlap limit of 400 mm and distribute welds on sides/ends.
   • Detail weld lengths, eccentricity and gusset connection sketch.
3. 14 Marks
   Design a double angle tension member connected on each side of a 10 mm thick gusset plate to carry an axial factored load of 375 kN. Use 20 mm black bolts. Assume shop connection.
   How to answer

   • Assume suitable double angle section and compute factored load 375 kN.
   • Check bolt shear, bearing and block shear for 20 mm black bolts, shop connection.
   • Check tensile yielding, rupture and block shear of angles per IS 800-2007.
   • Finalize section, number of bolts, gusset thickness and connection layout.
4. 14 Marks
   Determine the design axial load capacity of the column ISHB 300 @577 N/m if the length of column is 3 m and its both ends are pinned.
   How to answer

   • Obtain section properties of ISHB 300 @577 N/m from steel table.
   • Compute effective length for both ends pinned and slenderness ratios.
   • Determine design compressive stress fcd per IS 800-2007 buckling curves.
   • Compute design axial load capacity = A_e * fcd.
5. 14 Marks
   A roof of a hall measuring $8\, \text{m} \times 12\, \text{m}$ consists of 100 mm thick RC slab supported on steel I-beams spaced 3 m apart. The finishing load may be taken as $1.5\, \text{kN/m}^2$. Design the steel beam.
   How to answer

   • Compute dead load of 100 mm RC slab plus 1.5 kN/m^2 finishes and live load.
   • Compute factored UDL on beam with 3 m spacing and bending moment for span.
   • Select suitable I-beam for bending, shear and deflection per IS 800-2007.
   • Check shear, deflection and lateral stability.
6. 14 Marks
   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.
   How to answer

   • Compute factored shear from 50 kN/m UDL on 8 m effective span.
   • Determine bolt shear/bearing strength for 20 mm black bolts.
   • Design cleat angles and number of bolts to girder web ISMB 450.
   • Check block shear and detailing of framed connection.
7. 14 Marks
   Design a laced column with two channels back to back of length 10 m to carry an axial factored load of 1400 kN. The column may be assumed to have restrained in position but not in direction at both ends (hinged ends)
   How to answer

   • Assume two channels back to back and compute required area for 1400 kN factored load.
   • Determine spacing for equal radii of gyration and effective slenderness.
   • Design lacing bars and tie plates for transverse shear per IS 800-2007.
   • Check overall buckling and detail column section.
8. 14 Marks
   Write note on:

   1. i)Types of roof trusses
   2. ii)Purlins
   3. iii)Profile of gantry girder section
   4. iv)Deflection limits of gantry girders
   How to answer

   • Define each item with purpose and typical sketches.
   • Mention IS provisions / selection criteria for roof trusses, purlins, gantry girders.
   • State deflection limits for gantry girders with values.
   • Give examples/applications for each component.