Subject 2014 Question Paper — Government College of Engineering and T…

Instructions

• Attempt four questions in all, selecting at least two questions from each section.
• Assuming missing data suitably, if any.
• Use of IS 456, IS 800 and steel table is allowed.

Questions

Section A

• Q1. Design a two-way slab for a room $5.5\text{ m} \times 4.0\text{ m}$ clear size if the superimposed load is $5\text{ kN/m}^2$. Use M20 mix and Fe 415 grade steel. (i) Edges simply supported-corner not held down (ii) Edges simply supported-corners held down. [38 marks]
• Q2. Design a counter fort type retaining wall to the following particulars : Height of the wall above the general ground level = $5.50\text{ m}$ Safe bearing capacity of the soil = $160\text{ kN/m}^2$ Angle of repose of the soil $30^\circ$ Weight of soil = $16000\text{ N/m}^3$ Spacing of counter forts = $3\text{ m}$ centers. Use M20 and Fe 415. [38 marks]
• Q3. An unsymmetrical I-section prestressed concrete beam of span 9 meters. The beam has to carry a superimposed load of $20\text{ kN/m}$. The prestressing force is transmitted by tendons in two cables which are located at $120\text{ mm}$ from the soffit of the beam. In each cable the tendons consists of 14 wires of $5\text{ mm}$ diameter subjected to an initial stress of $1000\text{ N/mm}^2$. The sectional details are top flange, $250\text{ mm}$ wide and $100\text{ mm}$ thick; bottom flange $200\text{ mm}$ wide and $200\text{ mm}$ thick; thickness of web = $100\text{ mm}$; overall depth of beam = $800\text{ mm}$. Analyze the beam section at the centre for the stresses induced before and after the application of the superimposed load. Allow 15% loss of prestress. [38 marks]

Section B

• Q4. (a) What is geometry factor and how does it influence the strength of tension members? [12 marks]
• Q4. (b) Design an eccentric riveted connection to carry a load of $100\text{ kN}$ at an eccentricity of $200\text{ mm}$. Assume $20\text{ mm}$ dia. rivets with the two vertical rows with spacing of $80\text{ mm}$. Take thickness of bracket plate = $10\text{ mm}$. [25 marks]
• Q5. Design a built up column composed of two channel section placed back to back, carrying an axial load of $1345\text{ kN}$. Effective length of column is $5.95\text{ m}$ and also design double lacing system for the column. Take $f_y = 250\text{ N/mm}^2$. [37 marks]
• Q6. Design a grillage foundation for a column subjected to an axial load of $1500\text{ kN}$. The column section provided is ISWB 300 with a base plate $700\text{ mm} \times 700\text{ mm}$. The bearing capacity of soil is $120\text{ kN/m}^2$ assume missing data. [37 marks]
• Q7. (a) A laterally supported beam having an effective span of $8\text{ m}$ consists of ISMB 550 @ $103.1\text{ kg/m}$ and cover plate of $250\text{ mm} \times 16\text{ mm}$ connected to each flange by $20\text{ mm}$ dia. rivets. Determine the safe U.D.L. which the beam can carry in addition of its own self weight. [25 marks]
• Q7. (b) Differentiate between : (i) Bending of beam and Buckling of beam (ii) Web Buckling and Web Crippling [12 marks]