40 important question RCC

 Design Philosophies

 

Q1) If M20 is the grade of concrete, calculate the value of design strength of concrete considered for design.

Q2) Find out the design strength of Fe-415 grade steel.

 

Q3) If 25mm is the clear cover in 230mmx500mm beam, with 8 mm diameter stirrups and 3 nos.16 mm diameter longitudinal reinforcement arranged in single layer. Find out the following

a)  Effective / nominal cover

 

b)  Effective depth

 

c)  Spacing between longitudinal bars.

 

Q4 ) Using stress block parameter derive the values for limiting neutral axis depth, limiting depth and limiting moment for Fe-415,Fe-250,Fe-500.

Q5) What do you understand by working stress method and limit state method of design? Explain clearly

Design of Slabs

 

Q6) Differentiate between one way slab and two way slab.

 

Q7) An unrestrained reinforced concrete slab of effective dimension 4 m × 5m is simply supported on all four walls. It has to carry a characteristic live load of 12 kN/m² in addition to the dead load. Assuming M25 and Fe-415, thickness of the slab being 225 mm and finishing load of 1kN/m², what should be the design load as per limit state method and coefficients and moments along shorter span and longer span respectively

Q8) Design a reinforced concrete slab for a room of clear dimensions 3m x 7m supported on walls of 300 mm. Live load on the slab is 3kN/m² and floor finish of 1kN/m² Use M25 and Fe500. Sketch proper detailing to be provided

Q9)Design a continuous RC slab for a class room 7 m wide and 14 m long. The roof is to be supported on R.C.C. beams spaced at 3.5 m intervals. The width of beam should be kept 230 mm. The superimposed load 3 kn/m2 and finishing load expected is 1 kn/m2 use M30 concrete and Fe 415 steel.

Q10) Design a slab for a room of clear internal dimensions 3mx5m supported on walls of 300 mm thickness, with corners held down. Two adjacent edges of the slab are continuous and other

 

two discontinues. Live load on the slab is 3 kn/m2. Assume floor finish of 1kn/m2. Use M20 concrete and Fe 415 steel sketch the details of reinforcements.

Q11)Design a cantilever slab of span 2m to carry a imposed load of 2 km over its entire span. Take finishing lead as 1kn/m2. Use M20 and FE 415. Sketch reinforcement details.

Q12) Design a reinforced concrete slab for a room of size 4m x5m superimposed load is 5 kN/m. Use M20 concrete and Fe 415 steel. The edges are simply supported corners are held down.

Q13) Design reinforced concrete slab of size 6mx4m. Whose short edges corners are restrained at supports. The slab has to carry a live load of a 2kn/m and floor finish of 1 kN/m. Use M20 Fe- 415 and sketch reinforcement details.

Design of beams

 

Q14) Design a simply supported rectangular beam of length 5m supported on supports of  300 mm thick, with Live load of 15 Kn/m.

 

Q15) Design cantilever beam of span 2.5 m ,supported on column of width 400mm. Live load on the beam is 10 Kn/m.

 

Q16) Design a continous rectangular beam of span 8 m to carry dead load of 8 kN/m and live load of 18 kN/m. The beam is continous over more than 3 spans.

 

Q17) The rectangular beam of width, 300 mm is having overall depth of 600 mm. The concrete grade is M20 and the grade of reinforcing steel is Fe415. The tensile reinforcement is provided by 5-20 mm dia bars. The clear cover is 25 mm. The design shear force is 500 kN The design shear strength of concrete, τc, MPa for M20 grade of concrete is given as (100 Ast/bd ,τc, MPa) (0.25,0.36), (0.50, 0.48), (0.75, 0.56), (1.00, 0.62), (1.25, 0.67), (1.50, 0.72),

(1.75, 0.75), (2.00, 0.79), (2.25, 0.81), (2.50, 0.82). For M20 grade of concrete, the maximum shear stress permitted is 2.80 MPa. The spacing of stirrups for 2-legged stirrup of diameter 12 mm is closer to: (a) 100 mm (b) 200 mm (c) 300 mm (d) Increase depth of beam

 

Q18)A rectangular beam is to be simply supported on supports of 230 mm width. The clear span of the beam is 6 m. The beam is to have width of 300 mm. The characteristic super imposed load is 12 kN/m Using M20 concrete and Fe 415 steel design the beam.

 

Q19) Design a rectangular beam of section 230 mm x 600 mm of effective span 6 m. Effective cover for reinforcement should be kept as 50 mm. Imposed load on the beam is 40 kn/m.Use M20 concrete and Fe 415steel.

 

Q20)The portico of a guest house building consists of cantilever beams of effective span 3 m.

 

spaced at 2.5 m centre to centre. The beams support 120 mm thick slab. Live load on slab is

1.5 kn/m. Using concrete mix of M20 and steel Fe 415, design an intermediate beam.

 

Q21) Design a continuous rectangular beam of span 7 m to carry a dead load of 12 Kn/m and a live load of 18 kN/m. The beam is continuous over more than 3 span and is supported by columns. Use M20 concrete and Fe 415 steel.

 

Q22)A simply supported beam, supported over a span of 6m, carries a live load of 15 kN/m. Find out the depth of the beam and area of steel required if the width is equal to half of effective depth.

 

Q23)Design a doubly reinforced rectangular beam of section 230 mm x 550 mm(overall) and effective span of 6.5 m. Imposed load shall be assumed to be 38kN/m. Use M25 and Fe500. Sketch proper detailing to be provided.

 

Design of column

Q24) Explain the term slenderness ratio and classify columns based on slenderness ratio.

 

Q25) Design a column 3.8m long both ends hinged, to carry an axial load on 2000kN. Use M25 and Fe500.

 

Q26) Design a short axial column of effective length 3 m to carry an axial load of 1600 kN. Use M25 concrete and Fe 415 steel.

 

Q27) A R.C.C. square column is to be designed to carry a factored load of 2400 kN. The reinforcement is to be restricted to 2% of gross area. Adopting M25 concrete and Fe-415 steel, design the column. The column may be considered as short.

  Q28) . Determine the reinforcement to be provided in a square column 300 mm x 300 mm subject to uniaxial bending with the following data: Factored loadof 1000 kN, Factored bending moment - 120 kN-m Grade of concrete and Grade of steel M20 and Fe-415 .The reinforcement is to be provided on four faces equally. Use SP-16.

 

Q29)Determine the reinforcement required for a short column subjected to biaxial bending, using the following data: Cross section of the column 400 mm x 600 mm Concrete Mix: M 20 Steel: Fe-415.Factored load P 1800 kn Factored moment acting parallel to the larger dimension, 150 kN-m Factored moment acting parallel to the shorter dimension 120 kN-m.

 

Q30) Design a short column 450 mm square in section to carry an axial load of 800 kN with

 

moments of 60 kN-m and 40 kN-m about two and Fe-415 steel. Assume M20 concrete Steel: Fe-415

 

Q31) A square column 600 mm x 500 mm is reinforced with 2.4% steel. It is subjected to factored load of P-2000 &N and moment 200 kn-m. Check the adequacy of the section adopting M20 concrete and Fe-410 steel. The effective cover to steel may be taken as 50 mm and stool is to be provided equally on all the four sides.

 

Q32)Design a column of size 450 mm x 350 mm Using M25 and Fe-500 where effective length in x direction is 6.5m and effective length in y direction is 5.6 m .The column carry an axial load of 2000 kN .Moment in x direction 45 KN-m at top and 32 kN-m at bottom and Moment in y direction 48 kN-m at top and 36 kN-m at bottom. Sketch the reinforcement details.

Q33)A column 450 mm x 450 mm, is subjected to the factored loads P_u=1500kN M_ux=95 kN-m and M_uy=110kN-m.Design the reinforcement in the column assuming M25 and Fe-415 steel and effective cover 50 mm. Assume it is a short column.

 

Design of Footing

Explain various types of footings with sketches

Q34) Design an isolated footing of uniform thickness of a RC column bearing a vertical load of 850 KN and having a base of size 450 x 450 mm. the safe bearing capacity of soil may be taken as 110 kN/m².

Design of staircase

Briefly explain with the help of sketches different types of stairs

Q35)A straight stair is supported by beam on both sides of 230 mm width, with a horizontal span of 1.8m the riser are 150mm and tread 300mm take live load as 3kN/m². Use M25 and Fe500.Sketch the reinforcement details

 

Q36) Design a dog legged stairs for an office building in a room measuring 2.8m x 5.8 m vertical distance between floor is 3.6m.Width of flight is to be 1.25 m. Allow a live load of 3kN/m².Sketh the details of the reinforcement. Use M25 and Fe500. Stairs are supported on 230mm walls at the end of outer edges of landing slabs.

 

Q37)Design second flight of dog legged stairs, given the following data: Floor to floor height=3.6 m.

150 mm rise and 280 mm tread Imposed load= 3 kN/m²

Dimension of stair cases 2.4 mx 5.5 m. Assume stairs are to be supported on landing beams of width 250 mm parallel to stairs.

Use M20 concrete and Fe 415 steel. Sketch details of reinforcement.

Q38). Floor to floor vertical distance in a residential building is 3.2 m. Design a dog legged staircase, taking 160 mm rise and 250 mm tread as Step size. 2.5 kN/m² Imposed load. Width of stairs1.2 mDimension of stair case: 2.4 mx 4,75 m.Assume stairs are to be supported at the ends of landing slabs only, parallel to risers. M20 concrete and Fe 415 steel.