Andhra University 2007 B.E electronics - Question Paper

What is the advantage of limit state design over working

stress method ?

b) Under what conditions doubly reinforced beams are

adopted?

c) Reinforced concrete slabs are generally safe in shear. Comment

?

d) List the functions of transverse reinforcement in a reinforced

concrete beam.

e) What do you understand by development lenght ?

2. A reinforced concrete beam of rectangular part has to

carry a uniformly distributed load of eight kN/m over an effective

span of 10 m. Design the part using M20 and Fe415

grade steel, when i) there is no restriction on the size beam

part ii) the size of the part is restricted to 250 m x 500

effective. Use working stress method.

3. Determine the area of tensile reinforcement needed for singly

reinforced beam part of size 300 x 550 mm effective to

carry a factored moment of 180 kNm. The concrete is M20

and steel is Fe415 grade.

4. A series of beams placed at 2.5 m centres are supported on

masonry walls and the effective span of the beam is 5m. the

slab thickness is 100mm and ribs beneath the slab are 200mm

wide and 250 deep. If the slab and beams are so cast to act

together, determine the reinforcement at mid span for the T

beam to carry an imposed load of five kN/m2 of the slab. Use

concrete M20 and steel Fe415 grade.

II Year B.E./B.Tech Degree exam

REINFORCED CONCRETE STRUCTURES - I

Civil Engineering

Time : 3 hours Maximum : 75 Marks

15

5. A reinforced concrete rectangular beam part of 230mm

width and 450 mm overall depth is reinforced with four bars

of 16 mm of Feb415 grade, placed at an effective cover of

228 mm. Design he shear reinforcement if the beam is subject

to a uniformly distributed load of 50 kN/m over a simply

supported clear span of six m. Concrete is M20.

6. Design a reinforced concrete slab 4.5x 3.2 simply supported

on all 4 sides. It has to carry a characteristic live load of 4

kn/m2 in addition to its dead weight. Asume M20 and Fe415

steel. Also presume that exposure condition is mild.

7. A reinforced concrete column of unsupported length three m is

to be designed for a factored load of 1200 kN. Determine

the cross sectional dimensions of the column and the reinforcement

needed for the 2 cases.

i) There is no restriction on the column size.

ii) 1 side of the column is restriced to 230 mm.

The grade of concrete is M20 and steel is Fe415.

8. A solid footing has to transfer a total load of 800 kN. Assuming

Fe 415 and fck = 20 MPa, and safe bearing capacity

to be 200 kN/m2, design the footing.

Earning:   Approval pending.