ce-604-structural-design-and-drawing-jun-2025 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
   Explain about balanced, under reinforced and over reinforced sections with neat sketches as per limit state method.
   How to answer

   • Define balanced section: steel and concrete reach limiting strains simultaneously, Xu = Xu,lim
   • Define under-reinforced: steel yields first, ductile failure, Xu < Xu,lim
   • Define over-reinforced: concrete crushes first, brittle, Xu > Xu,lim
   • Neat sketches of strain and stress blocks for three cases with limit state assumptions
2. 14 Marks
   A hall has C/C dimensions of $21000\,mm \times 8000\,mm$ with beam spacing of $3500\,mm$ c/c. Overall dimensions of web is $300\,mm \times 475\,mm$ with tension steel 4#20 for end L - section. Thickness of slab $= 125\,mm$. Calculate $X_U$, $C_U$, $T_U$, lever arm, $M_R$ at collapse and the safe superimposed load on the slab excluding the self weight of the slab. The beam is exposed to moderate condition. Grade of concrete and steel is M25 and Fe550 respectively.
   How to answer

   • Determine effective flange width and effective depth for end L-section
   • Calculate Xu from equilibrium $C_U = T_U$
   • Calculate $C_U$, $T_U$, lever arm $z = d - 0.42X_U$
   • Calculate $M_R$ at collapse and convert to safe superimposed load excluding slab self-weight
3. 14 Marks
   Design a reinforced concrete footing for a rectangular column of section $300\,mm$ by $500\,mm$ supporting an axial factored load of $1500\,kN$. The SBC of the soil at site is $185 kN/m^2$. Adopt M20 grade concrete and Fe415 grade steel.
   How to answer

   • Determine required footing area from factored load and SBC
   • Fix plan dimensions and check punching and one-way shear
   • Calculate factored moments and required depth
   • Design reinforcement in both directions and sketch detailing
4. 14 Marks
   Design the reinforcement of a beam section, $230\,mm \times 500\,mm$ (effective depth), subjected to an ultimate twisting moment of $90\,kNm$, ultimate shear force of $120\,kN$ and ultimate BM of $200\,kNm$. Use M25 concrete and Fe415 steel. Sketch the reinforcement details.
   How to answer

   • Calculate equivalent shear and bending due to torsion + shear + BM per IS 456
   • Design longitudinal steel for combined moment and torsion
   • Design transverse stirrups for equivalent shear
   • Sketch cross-section with reinforcement details
5. 5 Marks
   aWhat are the various bond failure mechanisms. Explain.
   How to answer

   • Define bond and its importance in RCC
   • List mechanisms: adhesion, friction, mechanical interlock, splitting, pull-out
   • Explain each failure mode with factors
6. 9 Marks
   bFor a reinforced concrete tension member, a $12\,mm$ diameter rebar has to be lap spliced with a $20\,mm$ diameter rebar. Use M30 concrete and Fe500 grade steel. Design a suitable splice.
   How to answer

   • Calculate design bond stress for M30 per IS 456
   • Determine required lap length for 12 mm and 20 mm bars in tension
   • Check detailing rules for different diameters
   • Specify splice length, staggering and confinement
7. 14 Marks
   Design the reinforcement of a $450\,mm \times 450\,mm$ column of unsupported length $4.2\,m$ subjected to an axial load of $1600\,kN$ with bi-axial moments $150\,kNm$ and $100\,kNm$. Use M25 concrete and Fe 500 steel. Sketch the reinforcement details. https://www.rgpvonline.com
   How to answer

   • Check slenderness and effective length for 4.2 m unsupported length
   • Calculate eccentricity and additional moments for biaxial bending
   • Use interaction chart / SP-16 for axial + biaxial moment design
   • Design longitudinal and lateral ties and sketch details
8. 4 Marks
   aDraw the cross-section of singly reinforced rectangular beam and show the strain and stress diagrams.
   How to answer

   • Draw rectangular section with singly reinforcement
   • Show linear strain diagram with 0.0035 max concrete strain
   • Show rectangular-parabolic / equivalent stress block
9. 5 Marks
   bExplain the critical sections for design shear as per IS 456 with requisite sketches.
   How to answer

   • State IS 456 clause for critical section at distance d from face
   • Explain cases: point load, UDL, support conditions
   • Provide requisite sketches showing critical sections
10. 5 Marks
    cExplain the approaches for control of deflection in bending members as per IS 456. What are the measures for reducing deflection
    How to answer

    • State IS 456 span/effective depth ratios for control
    • Explain modification factors for tension and compression steel
    • List measures: increase depth, compression steel, higher grade, camber
11. 14 Marks
    Design the Dog legged staircase if supported on walls $300\,mm$ thick along landing slab at both ends. Floor finish $= 1\,kN/m^2$, Live load $= 5\,kN/m^2$, riser $R = 150\,mm$, tread $T = 300\,mm$, M20 and Fe415.
    How to answer

    • Fix going, riser, tread and effective span for dog-legged stair
    • Calculate loads: self-weight, floor finish 1 kN/m2, live 5 kN/m2
    • Calculate design moment and shear and required depth
    • Design main and distribution steel and landing slab detailing