MindTap Engineering, 1 term (6 months) Printed Access Card for Das/Sivakugan’s Principles of Foundation Engineering, 9th
9th Edition
ISBN: 9781337705202
Author: Das, Braja M., SIVAKUGAN, Nagaratnam
Publisher: Cengage Learning
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Chapter 2, Problem 2.10P
The soil profile at a site consists of 10 m of gravelly sand underlain by a soft clay layer. The water table lies 1 m below the ground level. The moist and saturated unit weights of the gravelly sand are 17.0 kN/m3 and 20.0 kN/m3, respectively. Due to some ongoing construction work, it is proposed to lower the water table to 3 m below the ground level. What will be the change in the effective stress on top of the soft clay layer?
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Problem 1
A ground profile consists of 2 m of silty sand underlain by 3 m of clay. The ground water table is 3 m below the ground surface. The sand has a unit weight of 14 kN/m3. The clay has unit weight of 16 kN/m3 above the water table and 20 kN/m3 below the water table.
a. Determine the total stress at bottom of the clay
b. Determine the pore water pressure at the bottom of the clay
c. Determine the effective stress at the bottom of the clay
Problem 2
50 ft thick sand is underlain by 25 ft clay. The ground water table, initially at the ground surface, was lowered to a depth of 25 ft below the ground. After such lowering, the degree of saturation of the sand above water table was lowered to 20%. Saturated and dry unit weight of sand are 135 pcf and 116 pcf respectively. The saturated unit weight of clay is 120 pcf.
a. What is the vertical effective pressure at the midheight of the clay layer before lowering of the water table in psf?
b. What is the vertical effective pressure at the…
A ground profile consists of 2m silty sand underlain by 3m of clay. The ground water table is 3m below the ground surface. The sand has a unit weight of 14kN/cum. The clay has a unit weight of 16kN/cum above the water table and 20kN/cum below the water table.
Determine the Total stress at the surface of the water table (kPa).
Determine the effective stress at the bottom of the clay layer (kPa).
Determine the effective stress 1m from the bottom of the clay layer (kPa).
Please answer this asap. For upvote. Thank you very much
sand layer 5m thick is underlain with a thick layer of clay. the sand has a void ratio of 0.52 and specific gravity 2.64. The clay has a water content of 42% and specific gravity of 2.64. The ground water table is located 3 m below the ground surface. The sand above the water table is 30% saturated.
a.) Determine the unit weight of the clay
b.) Determine the total stress at a depth of 10 m below the ground surface.
c.) Determine the effective stress at a depth of 10m below the ground surface.
Chapter 2 Solutions
MindTap Engineering, 1 term (6 months) Printed Access Card for Das/Sivakugan’s Principles of Foundation Engineering, 9th
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