CE-601 Structural Design and Drawing (RCC-I) - Jun 2026 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. 7 Marks
   aExplain the under, over and balanced section with respect to limit state of RCC Design.
   How to answer

   • Define balanced section: steel yields and concrete crushes simultaneously at limiting neutral axis.
   • Define under-reinforced: steel < balanced, ductile tension failure, steel yields first.
   • Define over-reinforced: steel > balanced, brittle compression failure, concrete crushes first.
   • Give limiting depth of neutral axis and failure behaviour as per IS 456 limit state.
2. 7 Marks
   bDiscuss the various assumption used in limit state method for design of compression member.
   How to answer

   • State plane sections remain plane assumption.
   • Maximum concrete strain 0.0035 and steel strain compatibility.
   • Stress block parameters, partial safety factors for materials.
   • Assumptions specific to short/long compression members and minimum eccentricity.
3. 7 Marks
   aDefine the following terms: characteristic loads, partial safety factor, and characteristic strength.
   How to answer

   • Define characteristic load as 95% exceedance value.
   • Define partial safety factor for loads and materials.
   • Define characteristic strength as 5% fractile strength.
   • Give IS 456 values for factors.
4. 7 Marks
   bList the steps involved in designing the strap footings.
   How to answer

   • Determine column loads, soil pressure and footing sizes.
   • Proportion strap beam for rigid transfer and shear/moment.
   • Design reinforcement for footings and strap beam.
   • Check shear, development length and detailing sketch.
5. 7 Marks
   aA beam $250\,mm \times 550\,mm$ effective is subjected to a factored bending moment of $300\,KNm$. Determine the area of steel required. Use M20 concrete and Fe 250 steel. Assume $d' = 50\,mm$, $d'/d = 0.1$.
   How to answer

   • Compute $R_u = M_u/(b d^2)$ and compare with $R_{u,lim}$ for doubly reinforced need.
   • Determine $d'/d$ and obtain steel stresses from design table.
   • Calculate $A_{st}$ and $A_{sc}$ using equilibrium equations.
   • Check minimum/maximum steel and detailing.
6. 7 Marks
   bA T beam floor system has $120\,mm$ thick slab supported on beams. The width of beam is $300\,mm$ and effective depth is $580\,mm$. The beam is reinforced with 8 bars of $20\,mm$ diameter. Use M20 grade of concrete and Fe 415 steel. The beams are spaced 3-meter center to center. The effective span of beam is 3.6 meter. Determine moment of resistance of the section, use M20 concrete.
   How to answer

   • Compute effective flange width $b_f$ from $l_0$, $b_w$ and spacing.
   • Compute $A_{st} = 8 \times \pi/4 \times 20^2$ and $x_u$ from equilibrium.
   • Check if neutral axis within flange or true T-beam.
   • Compute $M_u$ from concrete-steel couple for M20.
7. 14 Marks
   Design a slab for a hall of $3m \times 7\,m$ clear dimension to act as a roof for a live load of $2\,KN/m^2$ and floor finishes of $1.5\,KN/m^2$. The slab rest on brick wall of $230\,mm$ thick. Adopt M20 grade and Fe-415 Steel.
   How to answer

   • Determine one-way/two-way action from $l_y/l_x$ and effective spans.
   • Calculate factored load including self-weight, live load and finishes.
   • Calculate design moments and determine effective depth and $A_{st}$.
   • Check shear, deflection and detailing as per IS 456.
8. 14 Marks
   Design a cantilever slab for an overhang of $1.2\,m$. The imposed load on slab consists of $1\,KN/m^2$ of live load and weight of finishing is $800\,N/m^2$. Use M20 concrete and Fe 415 steel. Assume overall Depth $= 150\,mm$.
   How to answer

   • Calculate factored UDL including self-weight for 150 mm depth.
   • Compute maximum moment and shear at support $M_u = w_u l^2/2$.
   • Design main steel at top and check effective depth.
   • Provide distribution steel, development length and detailing.
9. 7 Marks
   aDesign an isolated Square footing for a column of $300\,mm \times 300\,mm$ carrying a factor axial load of $950\,KN$. Safe bearing capacity of soil is $150\,KN/m^2$. Use M25 Concrete and Fe-415 grade steel.
   How to answer

   • Convert factored load to service load and size footing from SBC.
   • Check one-way and two-way shear to fix effective depth.
   • Calculate bending moment and $A_{st}$ in both directions.
   • Check development length and detailing.
10. 7 Marks
    bDesign 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 minimum eccentricity for 4.2 m unsupported length.
    • Compute $P_{uz}$ and use biaxial interaction chart/formula.
    • Determine required $A_{sc}$ and select bar arrangement.
    • Design lateral ties and sketch reinforcement details.
11. 14 Marks
    Design a circular column of diameter $300\,mm$ to carry a factored axial load of $1500\,KN$ by using:(a) Helical reinforcement, (b) Hoop reinforcement. Use M20 concrete and Fe 415 steel.
    How to answer

    • Calculate required $A_{sc}$ and $A_c$ for 1500 kN factored load.
    • Design helical reinforcement for (a) per IS 456 pitch and volume condition.
    • Design lateral hoops/ties for (b) as tied column.
    • Compare and detail both with bar sizes and spacing.
12. 14 Marks
    Design the dog-legged staircase if supported on walls $300\,mm$ thick along the 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 Fe 415.
    How to answer

    • Assume storey height/span and compute waist slab effective span.
    • Calculate factored load with finishes and live load on going.
    • Design waist slab moment steel and landing slab.
    • Check shear, deflection and detailing of dog-legged stair.