Question

Four square footings, $b\times b$, each carrying a loading intensity of q are spaced close enough as shwon in the given figure :




The significant depth $D_s$, i.e depth of vertical stress contour, having a value of 0.2q will be

• A. 1.5 b
• B. 6.0b
• C. 1.5(B - 4b)
• D. 1.5 B

Answer 1

The correct option is D 1.5 B

Significant depth = 1.5 B
The region within the 0.20 q- isobar is called by Terzaghi the "seat of settlement". The depth below centre of footing in active zone (i.e., in ''seat of settlement") is 1.5B. For a larger footing more area will be affected so the settlement will be more.