The arrangement of soil layers are as shown below. Lower layer of sand is under artesian pressure. If effective stress at top of clay layer is half of the effective stress at top of lower layer of sand, then amount by which piezometric head in lower layer of sand rises above water table is: 4 m y= 17 kN/m 3 m Sand y = 20 kN/m³ [1m y= 21 kN/m' 6 m Clay 4 m Sand y= 20 kN/m

The arrangement of soil layers are as shown below. Lower layer of sand is under artesian pressure. If effective stress at top of clay layer is half of the effective stress at top of lower layer of sand, then amount by which piezometric head in lower layer of sand rises above water table is: 4 m y= 17 kN/m 3 m Sand y = 20 kN/m³ [1m y= 21 kN/m' 6 m Clay 4 m Sand y= 20 kN/m

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter9: In Situ Stresses

Section: Chapter Questions

Problem 9.4P

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A saturated clay layer has a thickness of 10 meters with a water content of 51% and a specific gravity 2.72. Determine the following: 1. Saturated unit weight of the clay * a. 21.46 kN/m³ b. 18.12 kN/m³ c. 16.87 kN/m³ d. 14.95 kN/m³ 2. total stress at depth of 10 meters a. 122.1 kPa b. 151.3 kPa c. 168.7 kPa d. 142.5 kPa 3. Effective stress at depth of 10 meters a. 42.1 kPa b. 70.6 kPa c. 68.7 kPa d. 82.5 kPa
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2) A soil profile consisting of three layers is shown in the Figure. A) Calculate the values of σ, u and σ' at points A,B,C and D if Layer 1: H1=5m, e=0.7, Gs=2.69 Layer 2: H2=8m, e=0.55, Gs=2.7 Layer 3: H3=3m, w=38%, e=1.2 B) What is the change in effective stress at point C if: If the water table drops by 2m? If the water table rises to the surface up to point A? Water level rises 3 m above point A due to flooding?
A soil profile consisting of three layers is shown in Table and Figure below i. Calculate the values of σ, u and σʹ at points A, B, C, and D. ii. Calculate the effective stress at c when water table drops by 1 m (consider γb= 15.5 for layer 2). iii. Calculate the effective stress at c when water table rises by 1 m above layer 1 due to flooding. (consider γsat= 16.5 for layer 1). Layer no. Thickness Soil parameters 1 H1 = 3.5 m γd = 15.5 kN/m3 2 H2 = 2.5 m γsat = 18 kN/m3 3 H3 = 3 m γsat = 18.5 kN/m3
A soil profile consists of a sand layer underlain by a clay layer, as shown. If the degree of saturation of the sand above water table was 50%. Saturated and dry unit weight of sand are 21.2 kN/m^3 and 18.22 kN/m^3 respectively. The saturated unit weight of clay is 18 kN/m3. Determine the total stress, pore pressure and effective stress at point A,B,C.
A soil stratum has two layers a 4m-thick dry sand underlain by a 5m–thick saturated sand. Dry unitweight and saturated unit weight of sand are respectively 16.21 KN/m3 and 20.88 KN/m3. a. What is the total stress at the bottom of the soil stratum?
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Caculate the total, neutral and effective stress (kPa) at the base of each soil layer listed below. Assume the water table rest 4 m below ground surface and that there is a capillary rise of 1 m above the water table. Provide your answers in kPa to 1 decimal place. Use 9.81 kN/m3 as the unit weight of water. Total Neutral Effective Silty Sand: 5m thick, γt = 17.5 kN/m3, γsat = 18.5 kN/m3, Blank 1 Blank 2 Blank 3 Clay: 4m thick, γt = 16.5 kN/m3, γsat = 17.8 kN/m3, Blank 4 Blank 5 Blank 6 Sand: 6m thick, γt = 17.3 kN/m3, γsat = 18.1 kN/m3, Blank 7 Blank 8 Blank 9