Anna University B.Arch www.annauniv.edu : Model Question Paper

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MODEL QUESTION PAPER
B. ARCH. DEGREE EXAMINATION
FIFTH SEMESTER
AR331 - DESIGN OF STRUCTURES –II

Time: 3 hrs. Maximum: 100 Marks.

http://www.annauniv.edu/academic/qp4.htm
http://www.annauniv.edu/academic/mqp5sem-ug/ar331.doc

Yield stress for Fe 415 grade reinforcement is 415 N/mm2 and for working stress method permissible tensile stress in reinforcement is 0.55 times the yield stress and permissible compressive stress in bending is one- third of the characteristic compressive strength of concrete. For the limit state of strength a load factor of 1.5 shall be used.

PART- A (10 x 2 = 20 marks)
Answer all Questions

1.Define the characteristic strength of materials and characteristic loads.
2.What are the different grades of concrete and reinforcement bars recommended for reinforced concrete structural members?
3.What are the assumptions made in the working stress method of analysis of reinforced concrete members?
4.Determine the ratio between the depth of neutral axis and the effective depth of reinforced concrete rectangular beams with Fe 415 grade tensile reinforcement for balanced sections.
5.What are the partial safety factors for strength of concrete and reinforcement bars?
6.Determine the limiting value of the ratio between the neutral axis depth and the effective depth of reinforced concrete beams with Fe 415 grade tensile bars for limit state of collapse.
7.What are the maximum and minimum percentages of tensile reinforcement recommended for reinforced concrete beams?
8.What are the factors governing the permissible shear stress in concrete and what is the distance of critical section for the design of shear reinforcement in beams generally carrying uniformly distributed load.
9.What are the span to effective depth ratios recommended for cantilever slabs, simply supported and continuous slabs to satisfy their approximate stiffness?
10.What are the minimum percentage and maximum spacing recommended for non-structural reinforcement for temperature and shrinkage and structural tensile reinforcement in reinforced concrete slabs.

PART - B (5 x 16 = 80 marks)

11.For the limit state strength design of a single reinforced concrete section derive the equation for xu/d, and limiting moment Mu, limit in terms of pt, fy, fck, where xu, is the actual depth of neutral axis, fy, and fck, are the characteristic strengths of tensile reinforcement and concrete, respectively, and pt, = As / b d, As is the area of tensile reinforcement, b and d are the width and effective depth, respectively, of the beam.

12.a) A simply supported single reinforced concrete rectangular beam of 250 m, width and 500 mm total depth with effective cover of 30 mm and effective span of 6 m carries uniformly distributed service load of 8 kN/m in addition to self weight.
Determine the following using working stress method with M 20 grade concrete and Fe 415 grade reinforcement: i) total design working load per metre, ii) Effective depth required for balanced section, iii) Area of tensile reinforcement for balanced section.
OR
12.b) A simply supported single reinforced rectangular beam of 300 mm, width x 600 mm depth with an effective span of 8 m carries two concentrated loads of 15 kN at the one–third points in the span. Determine the following using working stress method of design with M 20 grade concrete and Fe 415 grade reinforcement: i) maximum design moment due to concentrated loads and the self weight of the beam, ii) depth and area of tension reinforcement for the balanced section.