ST5101-Advanced Concrete Structures- UNIT4 IMPORTANT QUESTIONS

ST5101-Advanced Concrete Structures- UNIT4 IMPORTANT QUESTIONS

syllabus:-

UNIT IV INELASTIC BEHAVIOUR OF CONCRETE BEAMS AND COLUMNS 

Inelastic behaviour of concrete beams and Baker’s method, moment - rotation curves,ductility definitions, evaluation

PART – A 

1. What are the assumptions of baker’s method?
2. Define allowable rotation for inelastic analysis.
3. Define spandrel beams.
4. Explain the use of a crosstie with a sketch.
5. What are the types of cast in situ joints?
6. What do you understand by confined concrete?
7. What is meant by moment redistribution?
8. What are the advantages of moment redistribution?
9. Draw a typical moment rotation curve for simply supported beam under flexure.
10. Write down the moment rotation curvature relationship for balanced section.

PART – B 

1. A T- beam ABC is continuous over two spans of  8 m each and it carries uniformly distributed factored load of 75 kN/m. Assuming fck = 25 and fy = 500 (with bilinear stress – strain curve) check whether we can reduce the maximum moment by 30 % and redistribute the spans. Width of flange = 1000 mm, width of web = 300 mm, thickness of slab = 150 mm, D = 800 mm and d = 750 mm are given.

2. A circular column is 350 mm diameter. Find the diameter and spacing of hoops to be used for confident assuming that the concrete used is M20 and the steel is Fe 500. What will be the lateral reinforcements if the column is rectangular of 600 x 500 mm in size?

3. Write detailed notes on moment curvature relation of reinforced concrete sections.

4. What are the assumptions made and steps involved in Baker’s method of limit analysis of redundant RC frames? Explain.

5. A flat slab floor has panels 6 m x 5 m in X and Y directions between centres of columns which are 400 x 400 mm in size. It has an edge beam all around the periphery of 200 x 400 mm in which carrier an external wall of weight 6 kN/m. the slab thickness is 150 mm and the characteristic live load it has to carry is 5 kN/m2. The height of each storey is 3m. Analyze the exterior frame in 6 m direction and determine the distribution of moments.

6. A flat plate with 7.5 m x 6 m panels on 500 x 500 mm columns has a slab thickness of 165 mm, design for a characteristic load (DL+LL) of 9.3 kN/m2. Check the safety of slab in shear if M25 concrete and Fe 415 steel are used for its construction. How can we increase the shear capacity of the slab? 

7. Explain moment rotation curvature relationship for balanced, over, under reinforced beams with neat sketches?

8. A continuous beam has two spans each of 8m. The characteristic dead load is 15KN/m and live load is 25KN/m.Draw the bending moment envelope after maximum redistribution.

9. Determine the moment-curvature diagram for the flanged T-beam section.