The following concrete gravity wall of 7 m in height retains a sandy backfill. A sand sample from the backfill was brought to laboratory and tested in a direct shear device under a normal stress of 100 kPa and failure occurred at a shear stress level of 63.4 kl Using the Rankine theory, determine the total active earth pressure at the base of the wall when: a) the backfill is dry, b) the backfill is partially submerged in water for a water level at 3.5m from the base of the wall, c) the backfill is fully submerged in water, which means the water table is at the ground surface. Notes: - The saturated unit weight of the soil is 19 kN/m³ - The moist unit weight of the soil is 17 kN/m³ - The dry unit weight of the soil is 15 kN/m³ Summarize your results in this table: а) b) c) Total active earth pressure at the base of the wall (kPa)

The following concrete gravity wall of 7 m in height retains a sandy backfill. A sand sample from the backfill was brought to laboratory and tested in a direct shear device under a normal stress of 100 kPa and failure occurred at a shear stress level of 63.4 kl Using the Rankine theory, determine the total active earth pressure at the base of the wall when: a) the backfill is dry, b) the backfill is partially submerged in water for a water level at 3.5m from the base of the wall, c) the backfill is fully submerged in water, which means the water table is at the ground surface. Notes: - The saturated unit weight of the soil is 19 kN/m³ - The moist unit weight of the soil is 17 kN/m³ - The dry unit weight of the soil is 15 kN/m³ Summarize your results in this table: а) b) c) Total active earth pressure at the base of the wall (kPa)

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 13.1CTP

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