Question

A strap footing is to be provided for the two columns shown in the diagrams given below :





What is the length L of the left footing ? Take width of both the footings as 3.5 m and safe bearing capacity of soil as 250 $kN/m^2$

• A. 2.0 m
• B. 2.5 m
• C. 3.5 m
• D. 2.95 m

Answer 1

The correct option is D 2.95 m

Taking moment about $R_2$

$reaction{R}_1=\frac{3000\times 7}{(7-12)}=3620.69kN$

$Thus{R}_2=3000+4500-R_1=3879.31kN$

$forleftfooting,L_1=\frac{3620.69}{350\times 3.5}=2.95m$

$Forrightfooting,L_2=\frac{3879.31}{350\times 3.5}=3.17m$