CE-601 Structural Design and Drawing (RCC-I) - 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, under-reinforced and over-reinforced sections in limit state method
   • Give steel and concrete strain conditions and neutral axis comparison with limiting value
   • Draw neat cross-section with strain and stress block sketches for each type
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 T-beam
   • Calculate Xu, Cu, Tu, lever arm and MR at collapse
   • Calculate total factored load and safe superimposed load excluding slab self-weight
   • Check exposure and material grades M25 and Fe550
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

   • Calculate required footing area from SBC and factored load
   • Fix plan dimensions and check one-way and two-way shear
   • Design bending steel in both directions
   • Detail column-footing connection and sketch
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 per IS 456
   • Design longitudinal steel for combined moment and torsion
   • Design transverse stirrups for shear plus torsion
   • 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 splitting, pull-out and splitting-induced failures
   • Explain each mechanism with sketch
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 concrete
   • Determine development/lap length for 12 mm and 20 mm bars in Fe500
   • Adopt larger lap length with detailing provisions
   • Specify suitable lap splice detail
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.
   How to answer

   • Check slenderness and classify column for unsupported length 4.2 m
   • Use interaction charts for biaxial moments 150 kNm and 100 kNm
   • Calculate required longitudinal steel and laterals
   • Sketch reinforcement layout in section
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 reinforced steel
   • Show linear strain diagram with limiting values
   • Show rectangular-parabolic stress block with Cu and Tu
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 of point load, UDL and support conditions
   • Provide requisite sketches for each case
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/depth limits for deflection control
    • Explain modification factors for tension and compression steel
    • List measures like increasing depth, compression steel, 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 stair geometry from riser 150 mm and tread 300 mm with landing support
    • Calculate effective span, dead plus live and floor finish loads
    • Design waist slab thickness and main/distribution steel
    • Detail dog-legged layout with landing slab