Principles of Foundation Engineering, SI Edition
9th Edition
ISBN: 9781337672085
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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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
A ground profile consists of 2.0 meters silty
sand underlain by 3.0 meters of clay. The
ground water table is 3.0 meters below the
ground surface. The sand has a unit weight of 14
kN/cu.meter. The clay has a unit weight of 16
kN/cu.meter above the water table and 20
kN/cu.meter below the water table. Determine the
total soil stress at the bottom of the clay
layer.
A 10 m thick sand layer is underlain by 8 m thick clay layer. The groundwater is found to be at 3 m below
the surface at the present time. In the Past (long time ago) the ground water table was at 6 m below the
ground surface. The sand unit weight, ymoist=18 kN/m³ and the clay saturated density y«at = 17 kN/m³.
Required:
A) Total stress, pore pressure and effective stress at points A, B and C in Both Cases?
B) Calculate the over consolidation ratio (OCR) at the midpoint of the clay layer?
A
Present groundwater level
Sand
Y= 18 kN/m3
10m
3m
Current
B
Case
4m
A
Clay
y= 17 kN/m3
C
4m
A
Sand
Past groundwater level
Tem
10m
Y= 18 KN/m3
Previous
B
Case
4 m
A
Clay
y= 17KN/m
C
Chapter 2 Solutions
Principles of Foundation Engineering, SI Edition
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