A long excavation with vertical sides and depth-to-width ratio of 0.5 is to be made in a deep deposit of soft clay, having an undrained shear strength of 20 kPa and a saturated bulk unit weight of 17 kN/m³. Assuming that construction traffic will impose a surcharge of 10 kPa outside the excavation, determine the maximum depth of excavation that can be achieved, with side support, if a factor of safety of 1.5 against base heave is required.

A long excavation with vertical sides and depth-to-width ratio of 0.5 is to be made in a deep deposit of soft clay, having an undrained shear strength of 20 kPa and a saturated bulk unit weight of 17 kN/m³. Assuming that construction traffic will impose a surcharge of 10 kPa outside the excavation, determine the maximum depth of excavation that can be achieved, with side support, if a factor of safety of 1.5 against base heave is required.

Principles of Foundation Engineering (MindTap Course List)

9th Edition

ISBN:9781337705028

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter19: Braced Cuts

Section: Chapter Questions

Problem 19.7P

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