Principles of Foundation Engineering (MindTap Course List)
9th Edition
ISBN: 9781337705028
Author: Braja M. Das, Nagaratnam Sivakugan
Publisher: Cengage Learning
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Chapter 14, Problem 14.2P
In a piled raft, 450 mm diameter and 13 m long piles are placed in a rectangular grid at 1.60 m × 1.63 m spacing. Find the pile-raft interaction factor
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A group of piles as shown on the figure has a
cross section of 0.30 m x 0.30 m. It has a total
length of 15 m. The piles are embedded in a
homogeneous saturated clay with Cu = 70
kPa. Unit weight of clay is 18.8 kN/m³ and the
ground water table is located at a depth of
18 m. below the ground surface. Factor of
safety = 4. Compute the allowable load-
bearing capacity of the group of pile acting as
individual piles.
Qall
Clay
Cu70 kPa
70
15m
56 m-
LI-2.74 m
-Lz=3,96-
Ans. 2816.10 kN
A square pile group of 16 piles penetrates through a filled up soil of 3 m depth. The pile
diameter is 250 mm and pile spacing is 0.75 m. The unit cohesion of the material is 18
kN/m² and the unit weight of the soil is 15 kN/m². Compute the drag down force on the
group.
Determine the ultimate load capacity of a circular pile with diameter D = 20 cm installed in asaturated soft clay. The pile is embedded 10 m into the ground. According to measurements, thesoil exhibits an undrained shear strength according to the linear relationship: Su = 2+1.6z, wherez is the depth in meters and Su is the undrained shear strength in kPa. The soil's unit weight canbe assumed as 18 kN/m3
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Principles of Foundation Engineering (MindTap Course List)
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