Principles of Geotechnical Engineering (MindTap Course List)
9th Edition
ISBN: 9781305970939
Author: Braja M. Das, Khaled Sobhan
Publisher: Cengage Learning
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Chapter 16, Problem 16.10P
If the water table in Problem 16.9 drops down to 0.25 m below the foundation level, what would be the change in the factor of safety for the same gross allowable load?
16.9 A square footing is shown in Figure 16.18. Determine the gross allowable load, Qall, that the footing can carry. Use Terzaghi’s equation for general shear failure (Fs = 4). Given: γ = 17 kN/m3, γsat = 19.2 kN/m3, c′ = 32 kN/m3,
Figure 16.18
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Ex1: A footing is uniformly loaded with q = 100 kN/m² as shown in the figure.
Compute the vertical stress increments under Points A, B, and C at z = 10 m.
By
13.5
Footing
12m
Use Vertical stress Increment
under corner of rectangular
footing
7
(Plane view)
6
2. A square footing is shown in Figure 16.20. Determine the gross allowable load,
Qall, that the footing can carry. Use Terzaghi's equation for general shear failure
(F, = 3). Given: y = 105 lb/ft, Yat = 118 lb/ft, c' 0, = 35°, B = 5 ft,
D; = 4 ft, and h = 2 ft.
Unit weight of soil = y
Groundwater table
Yat
B
Figure 16.20
1. A circular footing 3 m in diameter is shown below.
[Soil Bearing Capacity] (
Assume the general shear failure and use a factor of safety 2.8. Determine the follow
N. = 25.13 , N, = 12.72, N, = 8. 34
a. The gross allowable bearing capacity.
b. Net Allowable bearing capacity
c. The safe load that the footing can carry.
Ground surface
Y = 18.5 kN/m³
C = 80 kPa
+ = 25°
1.1 m
D: = 1.8 m
Water table
Tse = 19.2 kN/m?
Diameter =
3 m
Chapter 16 Solutions
Principles of Geotechnical Engineering (MindTap Course List)
Ch. 16 - A continuous footing is shown in Figure 16.17....Ch. 16 - Refer to Problem 16.1. If a square footing with...Ch. 16 - Redo Problem 16.1 with the following: = 115...Ch. 16 - Redo Problem 16.1 with the following: = 16.5...Ch. 16 - Redo Problem 16.1 using the modified general...Ch. 16 - Redo Problem 16.2 using the modified general...Ch. 16 - Redo Problem 16.3 using the modified general...Ch. 16 - Redo Problem 16.4 using the modified general...Ch. 16 - Prob. 16.9PCh. 16 - If the water table in Problem 16.9 drops down to...
Ch. 16 - Prob. 16.11PCh. 16 - A square footing is subjected to an inclined load...Ch. 16 - A square footing (B B) must carry a gross...Ch. 16 - Redo Problem 16.13 with the following data: gross...Ch. 16 - Refer to Problem 16.13. Design the size of the...Ch. 16 - Prob. 16.16PCh. 16 - Prob. 16.17PCh. 16 - Refer to the footing in Problem 16.16. Determine...Ch. 16 - Figure 16.21 shows a continuous foundation with a...Ch. 16 - The following table shows the boring log at a site...
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