PROBLEM 5. A water tank is required to be constructed with a circular foundation having a diameter of 20m founded at a depth of 2m below the ground surface. The estimated distributed load on the foundation is 306 kN/m'. Assuming that the subsoil extends to a great depth and is isotropic and homogeneous, determine the stresses z at points ) z = 6m, r = 0, (i) z = 6m, r = 10m, (i) z = 20m, 7 0 and (iv) z = 20m, r = 10m, where r is the radial distance from the central axis. Use the Influence Diagram below to calculate the I. Neglect the effect of the depth of the foundation on the stresses. Influence value 1, (x100) 1.0 10 100 1.25 1.0 0.0 0.25 0.75 Note: Numbers on curves indicate value of r/Ro B = 2R. 10 io HR 8- 9- 10 Fig. 1. Influence Diagram for the Vertical Normal Stress at Various Points Under a Uniformly Loaded Circular Area (Foster and Ablvio, 1954) Depth z/R

PROBLEM 5. A water tank is required to be constructed with a circular foundation having a diameter of 20m founded at a depth of 2m below the ground surface. The estimated distributed load on the foundation is 306 kN/m'. Assuming that the subsoil extends to a great depth and is isotropic and homogeneous, determine the stresses z at points ) z = 6m, r = 0, (i) z = 6m, r = 10m, (i) z = 20m, 7 0 and (iv) z = 20m, r = 10m, where r is the radial distance from the central axis. Use the Influence Diagram below to calculate the I. Neglect the effect of the depth of the foundation on the stresses. Influence value 1, (x100) 1.0 10 100 1.25 1.0 0.0 0.25 0.75 Note: Numbers on curves indicate value of r/Ro B = 2R. 10 io HR 8- 9- 10 Fig. 1. Influence Diagram for the Vertical Normal Stress at Various Points Under a Uniformly Loaded Circular Area (Foster and Ablvio, 1954) Depth z/R

Principles of Foundation Engineering (MindTap Course List)

9th Edition

ISBN:9781337705028

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter9: Settlement Of Shallow Foundations

Section: Chapter Questions

Problem 9.9P

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