AC Question 1 (7 points) A soil profile consists of two layers. Soil properties

Question

AC Question 1 (7 points) A soil profile consists of two layers. Soil properties of the upper layer are H-8 m.7- 17 kN/m', and for the Australian College of Kawait lower layer l 1-20 m, Yut 21 kN/m) a) Plot the pore water pressure, effective stress, and total stress across the profile. b) Determine the average stress increase at a point 15 m below the ground surface due to 500 kPa loaded footing of 10 m by 5 m. Use the 2:1 and influence factor methods. Find the error between the two methods. c) What would be the final effective stress at the point after placing the footing?

Explanation / Answer

Total stress= z1y1-z2y2

z=8m, z2=20m

y1=17kN/m3, y2=21KN/m3

Now, total stress=z1y1+z2y2

=8*17+20*21

=136+420

=556Kn/m2

Unit weight of water= yw=9.81kN/m3

Neutral stress=z2yw

=20*9.81

=196.2KN/m2

Now effective stress=total stress- neutral stress

=556-196.2

=359.8KN/m2

Pore water pressure=(z1+z2)yw

=8*20*9.81

=1569.6KN/m2

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.