CE-702-D Structural Design and Drawing (RCC-II) - Dec 2024 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
   A five storey three bay building, having bay width $6\text{ m c/c}$, is to be located at Delhi. The thickness of the floor was $150\text{ mm}$ and live load on the floor is $5\text{ kN/m}^2$. Determine lateral forces on an inner frame due to wind load and earthquake loads. Using the following data: Frame Spacing $= 4.5\text{ m c/c}$ Height of ground floor $= 4.2\text{ m}$ Height of another floors $= 3.7\text{ m}$ Floor Finish $= 4\text{ cm}$ Columns $= 300\text{mm} \times 600\text{mm}$ Beam $= 300\text{mm} \times 400\text{ mm}$
   How to answer

   • Define seismic weight and wind pressure per IS:875 / IS:1893
   • Compute dead load of slab, finish, beams, columns per frame
   • Determine earthquake lateral forces by seismic coefficient method
   • Determine wind lateral forces by design wind pressure
   • Distribute storey shears to inner frame
2. 14 Marks
   Design a counterfort type retaining wall with the following data: Height of the wall above the ground level $= 4\text{m}$, Safe bearing capacity of soil at site $= 160\text{ kN/m}^2$, angle of internal friction $= 33^\circ$, density of soils $= 16\text{ kN/m}^3$, spacing of counterforts $= 3\text{ m c/c}$. Adopt M20 grade concrete and Fe415 HYSD grade of steel. Sketch the details of the reinforcement in the walls.
   How to answer

   • Determine earth pressure coefficient Ka and stem/base dimensions
   • Check stability against overturning, sliding and base pressure
   • Design vertical stem, toe, heel and counterfort as T-beam
   • Detail main, distribution and shear reinforcement
   • Sketch reinforcement details in walls
3. 14 Marks
   Design a rectangular water tank $5\text{ m} \times 4\text{ m}$ with the depth of storage $3\text{m}$, resting on ground and whose walls are rigidly joined at vertical and base. Free at top. Assume M20 concrete and Fe415 steel. Sketch the details of the reinforcement in the tank using IS code method. Assume suitable data.
   How to answer

   • Fix wall thickness and base conditions per IS:3370
   • Compute hydrostatic and earth pressures if any
   • Calculate bending moments in vertical and horizontal directions
   • Design reinforcement for walls and base slab
   • Sketch reinforcement details
4. 14 Marks
   Explain the difference between Silo and Bunker. Also discuss the design of hopper bottom of a bunker.
   How to answer

   • Define Silo vs Bunker by depth/plane of rupture criterion
   • Tabulate differences in shape, loading, Janssen vs Rankine
   • Explain hopper bottom loads and pressure distribution
   • Outline design steps for hopper slab/beam reinforcement
5. 14 Marks
   A pretensioned prestress concrete beam of $6\text{m}$ span has cross section of $300\text{ mm} \times 500\text{ mm}$, is prestressed with $155\text{ kN}$ force at transfer. The cable has cross sectional area of $1500\text{ mm}^2$ of steel and has a parabolic profile with a maximum eccentricity of $200\text{ mm}$ at the mid span. Determine the loss of prestress, given that: $Es = 2.0 \times 10^5\text{ N/mm}^2$ and $Ec = 3.1 \times 10^4\text{ N/mm}^2$.
   How to answer

   • Compute section properties and prestressing stress
   • Calculate elastic shortening loss using modular ratio
   • Account for parabolic profile effect if required
   • Determine net loss of prestress at transfer
   • State assumptions for Es, Ec
6. 14 Marks
   Design a slab bridge with carriage way of $12\text{ m}$ with Kerbs only for an effective span of $6.0\text{ m}$ for IRC 70 loading. Concrete used is M25 and HYSD bar of grade Fe415 are used.
   How to answer

   • Fix effective span, width, wearing coat and dispersion
   • Compute dead load and IRC 70 tracked/wheeled moments and shears
   • Apply impact and distribution factors
   • Design slab thickness and main/distribution steel in M25/Fe415
   • Detail kerbs and check shear
7. 7 Marks
   aCalculate the earth pressure acting on a $5\text{m}$ high cantilever wall.
   How to answer

   • State Rankine/Coulomb active pressure formula
   • Assume soil parameters if not given
   • Compute Ka and pressure distribution triangular
   • Calculate total thrust and point of application
8. 7 Marks
   bWhat are the functions of retaining wall? Discuss the component of counterfort type retaining wall.
   How to answer

   • List functions: retain soil, prevent erosion, support surcharge
   • Identify components: stem, toe, heel, counterfort, key
   • Explain load transfer in counterfort type
   • Note advantages for high walls
9. 14 Marks
   Write short notes on any four of the following:

   1. i)Pre and Post Tensioning System
   2. ii)Cantilever retaining wall
   3. iii)Types of water tank
   4. iv)Losses in prestressing
   5. v)Methods of prestressing
   How to answer

   • Select any four topics with definition and principle
   • Give sketches/classification and key formulas
   • Mention IS code provisions and applications
   • Conclude with advantages/limitations