A fixed retaining wall is backfilled to height of 10m with dry cohesionless sand. The resulting backfill has a unit weight of 18kN/m³ and a drained angle of internal friction of 36". a. Prior to backfilling, what is the horizontal stress (kPa) at a depth of 10m below the final elevation of the finished backfill? b. Assuming that the overconsolidation ratio of the soil in the backfill at a depth 10m below the surface is equal to 2.0, what is the corresponding effective horizontal stress at a depth of 10m below the top of the backfill? c. If a 200kN/m² surcharge is then applied to the surface of the backfill in the previous item (b), what will be the effective horizontals stress (kPa) at a depth of 10m below the top of the backfill? d. If the surcharge in the previous item (c) is reduced to 25kPa, what will be the effective horizontal stress at a depth of 10m below the top of the backfill? e. If the surcharge in the previous item (d) is increased to 100kPa, what will be the effective horizontal stress at a depth of 10m below the top of the backfill?

A fixed retaining wall is backfilled to height of 10m with dry cohesionless sand. The resulting backfill has a unit weight of 18kN/m³ and a drained angle of internal friction of 36". a. Prior to backfilling, what is the horizontal stress (kPa) at a depth of 10m below the final elevation of the finished backfill? b. Assuming that the overconsolidation ratio of the soil in the backfill at a depth 10m below the surface is equal to 2.0, what is the corresponding effective horizontal stress at a depth of 10m below the top of the backfill? c. If a 200kN/m² surcharge is then applied to the surface of the backfill in the previous item (b), what will be the effective horizontals stress (kPa) at a depth of 10m below the top of the backfill? d. If the surcharge in the previous item (c) is reduced to 25kPa, what will be the effective horizontal stress at a depth of 10m below the top of the backfill? e. If the surcharge in the previous item (d) is increased to 100kPa, what will be the effective horizontal stress at a depth of 10m below the top of the backfill?

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter13: Lateral Earth Pressure: At-rest, Rankine, And Coulomb

Section: Chapter Questions

Problem 13.21P

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