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Total No. of Pages: 2 7622

Register Number:

Name of the Candidate:

P.G.dIPLOMA EXAMINATION - 2012

(CONCRETE TECHNOLOGY AND dESIGN OF CONCRETE STRUCTURE)

(paper – II)

520. STRUCTURAL CONCRETE DESIGN-I

(Candidates joining during 2008-2009 and before)

Dec.) (Time: 3 Hours

Maximum: 100 Marks

Answer ONE FULL question from each unit (5×20=100)

All questions carry equal marks

UNIT-I

Discuss about various stress factors and load factors to be considered in the design of reinforced concrete structures. Also discuss about the materials used in concrete with their required qualities.
(OR)
Compare the working stress method and ultimate load design and explain the design concept of the working stress method.
UNIT-II
A reinforced concrete beam of span 6m has a rectangular section 250mm wide and 500mm depth. The beam is reinforced with 3 bars of 16mm diameter on the tension side at the effective depth of 450mm; and 3 bars of 10mm diameter on the compression side at a cover of 50mm from the compression face. If M20 grade concrete and Fe415 grade steel is used. Estimate the maximum permissible live load in the beam using working stress method.
(OR)
A reinforced concrete simply supported beam of effective span 6.0m is subjected to a uniformly distributed load of 20kN/m run. Design the beam. Concrete grade M20 and Fe415 steel are used using working stress method.
UNIT-III
Design a one way slab with clear span of 4.0m simply supported on 200mm thick concrete masonry walls to support a live load of 4kN/m2. Adopt M20 grade concrete and Fe415 HYSD bars using working stress method.
(OR)
Design a two way slab for an office floor of size 5.5m×5.0m with discontinuous and simply supported edges on all the sides with corner prevented form lifting and supporting a service live load of 6kN/m2. Adopt M20 grade concrete and Fe415 HYSD Bars Using Working Stress Method.
UNIT-IV
A column 400mm×400mm×6m long has to support a load of 875kN. Find the necessary reinforcement for the column. Use M15 concrete. For a short column, the safe stresses in concrete and steel are 4N/mm2 and 130N/mm2 respectively.
Design a reinforced concrete rectangular footing for a rectangular column section 300mm×400mm supporting an axial factored load of 1600kN. The safe bearing capacity of the soil at site is 200kN. Adopt M20 grade concrete and Fe415 HYSD bars using working stress method.
UNIT-V
Design a dog-legged stair case(Slab type) using working stress method for an office building assuming floor to floor
height of 3.4m
width of flight =1.0m
landing width =1.0m
Riser S=150mm , tread =300mm
Adopt M20 grade concrete and Fe415 HYSD bars. Assume a live load of 6kN/m2. Assume the landing to be supported only on two edges perpendicular to the risers.
The main stair of an office building has to be located in a stair measuring 3.5m×5.5m. The vertical distance between the floor is 3.75m. Design the stairs, allowing a live load of 3kN/m2. Use M15 concrete and mild steel reinforcement.

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