PRINCIPLES OF GEOTECH.ENGINEERING >LL+M
9th Edition
ISBN: 9781337583879
Author: Das
Publisher: CENGAGE L
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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
A square footing is proposed to be constructed on the silty sand layer as shown in Figure
Q2. If the gross load (Qall) is 600 kN, check whether the foundation can carry the load or
not. (Use Terzaghi's bearing capacity equation with general shear failure and FS = 3).
2.
Qall
Silty Sand
1.5 m
y 19 kN/m
c' 8 kN/m2
= 25°
Ground Water
0.5 m
1.2 m
Level
Kar 19.0 kN/m'
Figure Q2: A Square Footing
Chapter 16 Solutions
PRINCIPLES OF GEOTECH.ENGINEERING >LL+M
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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