JNTU Kakinada B-Tech 3-1 RT31013 I DESIGN AND DRAWING OF REINFORCED CONCRETE STRUCTURES R13 April 2018 Question Paper

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Code No: RT31013
III B. Tech I Semester Supplementary Examinations, May-2018
DESIGN AND DRAWING OF REINFORCED CONCRETE STRUCTURES (Civil Engineering)Time: 3 hours Max. Marks: 70
Answer any ONE Question from Part ? A and any THREE Questions from Part ? B
Use of IS: 456-2000 and design charts from SP-16 is allowed.
For all designs adopt Limit State Method
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PART ?A
1 Design the reinforcements in a circular column of diameter 350mm with helical
ties to support a factored load of 1600kN. The column has an unsupported length
of 3.5m and is braced against side sway. Adopt M-25 grade concrete and Fe-500
grade reinforcement.
[28M]
2 Design a combined footing for the two columns of a multistory building. The
columns of size 400mm?400mm transmit a working load of 800kN each and they
are spaced at 5m centers. The safe bearing capacity of soil at site is 200kN/m
2
.
Adopt M-20 grade concrete and Fe-415 grade reinforcement. Sketch the details of
reinforcements in the combined footing.
[28M]
PART ?B
3 a) Explain the terms: neutral axis depth factor, modular ratio, lever arm coefficient
and moment of resistance with respect to reinforced concrete sections.
[7M]
b) What are the various serviceability states and why they should be considered in
design?
[7M]
4 Determine the moment of resistance of a tee-beam having the following section
properties:
Effective width of flange=2500mm
Depth of flange=150mm
Width of rib=300mm
Effective depth=800mm
Area of steel:6 bars of 25mm diameter
Materials:M-20grade concrete
Fe-415 HYSD bars.
[14M]
5 A simply supported reinforced concrete beam of rectangular section 250mm wide
by 450mm overall depth is used over an effective span of 4m. The beam is
reinforced with 3 bars of 20mm diameter Fe-415 HYSD grade steel at an effective
depth of 400mm. Two hanger bars of 10mm diameter are provided. The self
weight together with the dead load on the beam is 10kN/m. Using M-20 grade
concrete, compute:
i) The short term deflection
ii)The long term deflection according to the provisions of the IS:456-2000 code.

1 of 2
[14M]
R13
SET – 1
|”|”|||”|”’|||’|

Code No: RT31013
III B. Tech I Semester Supplementary Examinations, May-2018
DESIGN AND DRAWING OF REINFORCED CONCRETE STRUCTURES (Civil Engineering)Time: 3 hours Max. Marks: 70
Answer any ONE Question from Part ? A and any THREE Questions from Part ? B
Use of IS: 456-2000 and design charts from SP-16 is allowed.
For all designs adopt Limit State Method
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PART ?A
1 Design the reinforcements in a circular column of diameter 350mm with helical
ties to support a factored load of 1600kN. The column has an unsupported length
of 3.5m and is braced against side sway. Adopt M-25 grade concrete and Fe-500
grade reinforcement.
[28M]
2 Design a combined footing for the two columns of a multistory building. The
columns of size 400mm?400mm transmit a working load of 800kN each and they
are spaced at 5m centers. The safe bearing capacity of soil at site is 200kN/m
2
.
Adopt M-20 grade concrete and Fe-415 grade reinforcement. Sketch the details of
reinforcements in the combined footing.
[28M]
PART ?B
3 a) Explain the terms: neutral axis depth factor, modular ratio, lever arm coefficient
and moment of resistance with respect to reinforced concrete sections.
[7M]
b) What are the various serviceability states and why they should be considered in
design?
[7M]
4 Determine the moment of resistance of a tee-beam having the following section
properties:
Effective width of flange=2500mm
Depth of flange=150mm
Width of rib=300mm
Effective depth=800mm
Area of steel:6 bars of 25mm diameter
Materials:M-20grade concrete
Fe-415 HYSD bars.
[14M]
5 A simply supported reinforced concrete beam of rectangular section 250mm wide
by 450mm overall depth is used over an effective span of 4m. The beam is
reinforced with 3 bars of 20mm diameter Fe-415 HYSD grade steel at an effective
depth of 400mm. Two hanger bars of 10mm diameter are provided. The self
weight together with the dead load on the beam is 10kN/m. Using M-20 grade
concrete, compute:
i) The short term deflection
ii)The long term deflection according to the provisions of the IS:456-2000 code.

1 of 2
[14M]
R13
SET – 1
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Code No: RT31013

6 Design a two-way slab 4m?6m continuous on all edges and supported on 300mm
wide beams to serve as an office floor. Adopt M-25 grade concrete and Fe-500
HYSD bars.
[14M]
7 Design a waist slab type dog legged staircase for an office building using the
following data:
Height between floors=3.2m
Tread=270mm and riser=160mm
Width of flight = landing width=1.25m
The stairs are supported on 300mm load bearing masonry walls at the outer edges
of the landing, parallel to the risers.
Materials: M-20 grade concrete and Fe-415 HYSD bars.
[14M]

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2 of 2
R13
SET – 1