A layer of sand extends from ground level to a depth of 9m and overlies a layer of clay, of very low permeability, 6m thick. The water table is 6m below the surface of the sand. The saturated unit weight of the sand is 19.5 kN/m³ and that of the clay 20 kN/m³; the unit weight of the sand above the water table is 17 kN/m³. Over a short period of time the water table rises by 3m and is expected to remain permanently at this new level. Determine the effective vertical stress at depths of 8 and 12m below ground level (a) immediately after the rise of the water table and (b) several years after the rise of the water table.. WT(2) SAND 3m WT(1) CLAY 12 m

A layer of sand extends from ground level to a depth of 9m and overlies a layer of clay, of very low permeability, 6m thick. The water table is 6m below the surface of the sand. The saturated unit weight of the sand is 19.5 kN/m³ and that of the clay 20 kN/m³; the unit weight of the sand above the water table is 17 kN/m³. Over a short period of time the water table rises by 3m and is expected to remain permanently at this new level. Determine the effective vertical stress at depths of 8 and 12m below ground level (a) immediately after the rise of the water table and (b) several years after the rise of the water table.. WT(2) SAND 3m WT(1) CLAY 12 m

Principles of Foundation Engineering (MindTap Course List)

9th Edition

ISBN:9781337705028

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter2: Geotechnical Properties Of Soil

Section: Chapter Questions

Problem 2.15P

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Q A layer of sand extends from ground level to a depth of 9 m and overlies a layer of clay, of very low permeability, 6 m thick. The water table is 6 m below the surface of the sand. The saturated unit weight of the sand is 19 kN/m3 and that of the clay 20 kN/ m3; the unit weight of the sand above the water table is 17 kN/m3. Over a short period of time the water table lowers by 3 m and is expected to remain permanently at this new level. Determine the effective vertical stress at depths of 8 and 12 m below ground level (a)immediately after the lowering of water table and (b)Several years after the lowering of the water table. Explain your answer for each part.
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a dense silt layer has the following properties: void ratio = 0.50, effective diameter d10 = 10 um, capillary constant c = 0.20 cm2. free ground water level is 8.0 m below the ground surface. find the vertical effective stress in kpa at 5m depth. assume unit weight of solids = 26.5 kn/m3 and that the soil = 26.5 kn/m3 and that the soil above the capillary action rise and ground surfaces is partially saturated at 50% from the problem above, find the vertical effective stress at 10m depth. assume unit weight of solids=26.5kN/m3 and that the solid above the capillary action rise and ground surface is partially saturated at 50%.
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