Problems on Combined stress

Short Answer Questions:

1.What do you mean by direct stress and bending stress?

2 Draw stress distribution across the section due to Bi axial bending stress and direct stress.

3 Find core diameter of a solid circular section, if diameter is ‘d’

4 Explain about the term kernel and determine the size of kernel for a rectangular section 200 mm x 300mm

5 Explain the conditions for stability of dam.

6 Find core diameter of a hollow section, if external and internal diameter are ‘D’ and ‘d’.

Assignment :

1 A hollow rectangular column of external depth of 1 m and external width 1 m is 10 cm thick.. Calculate the maximum and minimum stress in the section of the column, if vertical load of 200 kN is acting with an eccentricity of 20 cm.

2 A short column of external diameter 40 cm and internal diameter 20 cm carries an eccentric load of 80 kN. Find the greatest eccentricity which the load can have without producing tension on the cross –section.

3 Masonry dam 9m high, 1.5m wide at top and 6m wide at the base retains water to a depth of 7.5m, the water face of the dam being vertical. Find maximum and minimum stress intensities at the base. The weight of water is 9.81kN/m3 and weight of masonry is 24kN/m3

4 A column is rectangular in cross section 300 x 400 mm .The column carries an eccentric loading of 360kN on one diagonal at a distance of quarter diagonal length from a corner. Calculate the stresses at all four corners. Also draw stress distribution diagram for any side

5 A square chimney, 30 m high, has a flue opening of size 1.5 m x 1.5 m. Find the minimum width required at the base for no tension if the masonry weights 20 kN/m2 and the wind pressure is 1.5 kN/m2. The permissible stress in the masonry is 1kN/m2.

6 A solid round bar 3 m long and 5 cm in diameter is used as a strut with one end is fixed and other is hinged. Determine the crippling load.

Take E = 2x105 N/mm2.

Comments

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