A trench is to be excavated in a clay soil with y at = 20 kN/m² and s, = 15 kPa. (a) Determine the theoretical maximum depth of the trench without lateral support. (b) It was decided to use a bentonite slurry of unit weight y, to fill the trench as excavation proceeds. Show that the theoretical maximum depth of the trench is H, = unit weight of the soil and s, is the undrained shear strength. (c) How much deeper can the trench be excavated by using a bentonite slurry of y; = 11 kN/m?? - where y a is the saturated Yrat - Yf

A trench is to be excavated in a clay soil with y at = 20 kN/m² and s, = 15 kPa. (a) Determine the theoretical maximum depth of the trench without lateral support. (b) It was decided to use a bentonite slurry of unit weight y, to fill the trench as excavation proceeds. Show that the theoretical maximum depth of the trench is H, = unit weight of the soil and s, is the undrained shear strength. (c) How much deeper can the trench be excavated by using a bentonite slurry of y; = 11 kN/m?? - where y a is the saturated Yrat - Yf

Principles of Foundation Engineering (MindTap Course List)

8th Edition

ISBN:9781305081550

Author:Braja M. Das

Publisher:Braja M. Das

Chapter10: Drilled-shaft Foundations

Section: Chapter Questions

Problem 10.10P

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