An R.C. square footing of side length 2 m and uniform effective

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An R.C. square footing of side length 2 m and uniform effective depth 200 mm is provided for a 300 mm × 300 mm column. The line of action of the vertical compressive load passes through the centroid of the footing as well as of the column. If the magnitude of the load is 320 kN, the nominal transverse (one way) shear stress in the footing is

1. 0.26 N/mm²
2. 0.30 N/mm²
3. 0.34 N/mm²
4. 0.75 N/mm²

Correct Option: A

For transverse shear, critical section is at a distance of 200 mm (d) from face for column.

Uniform thrust due to applied load on the footing from soil, P₀

P₀ =	320 × 10³	= 0.08 N/mm²
	2000 × 2000

Nominal transverse shear force on footing

= P₀ × B ×		1	(B - b) - d
		2

= 0.08 × 2000 ×		1	(2000 - 300) - 200		= 104000 N
		2

∴ shear stress = 104000/Bd

=	104000	= 0.26 N/mm²
	2000 × 200