Cochin University of Science and Techology (CUST) 2005-5th Sem B.Tech Civil Engineering , , Design of Structures I - Question Paper
BTS(C) -V -05-061 (C)
B.Tech. Degree V Semester Examination, November2005
CE 502 (A/B) DESIGN OF STRUCTURES I
( 2002 Admissions )
Maximum Marks: 100
Time: 3 Hours
(Use of IS456 and SP 16 permitted. All designs are to be in the Limit State Method)
a) Explain the following terms:
i) Limit State Design ii) Ultimate load theory
iii) Elastic theory iv) Characteristic strength
v) Characteristic load vi) Partial safety factor
vii) Mu (lin) for Fe 250 and Fe 415 steels and M2o mix. (15)
b) Design a rectangular beam to resist a bending moment equal to 45kNm using
i) M)5 mix and Fe 4! 5 grade steel.
ii) M2o mix and Fe 415 grade steel (20)
OR
a) Find the moment of resistance of a beam section 20cm by 60cm deep if it is reinforced with 2-20mm bar in compression and tension, each at an effective cover of 50mm.
Use M15 mix and Fe 415 grade steel. (IS)
b) Design a double reinforced section for a rectangular beam and midspan having a simply supported effective span of 4m. The super imposed load is 40kN/m and size
of beam is limited to 25cm x 40cm overall. Assume suitable data. (20)
a) Explain the following with sketches.
III
i) Diagonal tension failure
ii) Flexural shear failure
iii) Diagonal compression failure
iv) Typical failure modes in torsion. (12)
b) The beams shown in figures are subjected to factored shear force of 200kN. If cfrtt =20N/mm2 and <jv =415N/mm2. Calculate the shear reinforcement.
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(23)
IV a) A supply supported beam is 25 cm by 50 cm and has 2-20 mm TOR bars going into the support. If the shear force at the centre of support is 11 OkN at working loads, determine the anchorage length. Assume M20 mix and Fe 415 grade TOR steel.
b) Design a continuous one-way slab having three equal spans of 3m each as shown in the figure with the following data: imposed load = 2.5kN/m2. Use M15 and Fe 415 grade steel.
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Design a short column under biaxial bending with the following data:
V a)
Size of column Concrete grade Steel grade Factored load Factored moment
45 x 45 cm M15 Fe 415
Pu- lOOOkN Mux = 75 kNm Muy = 60 kNm
Moments due to minimum eccentricity are less than the values given above.
Reinforcement is distributed equally on four sides. (15)
Design a circular column to carry an axial load of 1500kN using (i) lateral ties
b)
VI a) b)
(ii) helical reinforcement. Use M2j mix and Fe 415 grade steel. (15)
OR
A 4m high column is effectively held in position at both ends and restrained against rotation at one end. Its diameter is restricted to 40cm. Calculate the reinforcement if it is required to carry a factored axial load of 1500 kN. Use M2o mix and Fe 250 grade steel. (10)
Design a stair flight for the staircase shown in the figure. Take superimposed loads as 2QNJmm2 and cr =415Ni mm2.
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Attachment: |
| Earning: Approval pending. |
