Fundamentals of Geotechnical Engineering (MindTap Course List)
5th Edition
ISBN: 9781305635180
Author: Braja M. Das, Nagaratnam Sivakugan
Publisher: Cengage Learning
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Chapter 19, Problem 19.8P
For the drilled shaft described in Problem 19.7, estimate the total elastic settlement at working load. Use Eqs. (18.45), (18.47), and (18.48). Assume that Ep = 20 × 106 kN/m2, μs = 0.3, Es = 12 × 103 kN/m2, ξ = 0.65 and Cp = 0.03. Assume 80% mobilization of skin resistance at working load. (See Part c of Problem 19.7)
19.7 Figure 19.16 shows a drilled shaft without a bell. Here, L1 = 6 m, L2 = 7 m, Ds = 1.5 m, cu(1) = 50 kN/m2, and cu(2) = 75 kN/m2. Find these values:
a. The net ultimate point bearing capacity. Use Eqs. (19.23) and (19.24)
b. The ultimate skin resistance. Use Eqs. (19.26) and (19.28)
c. The working load, Qw (FS = 3)
FIG. 19.16
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Take o, = 580 kPa
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Part B
Determine the shear stress acting on the inclined plane AB.
Express your answer to three significant figures and include the appropriate units.
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1. Triaxial compression tests are done on quartzite rocks, the results are shown below.
(0₁+03)/2 -964.25 14500 19575 23200 29000 43210 63075 psi
(01-03)/2 964.25 14500 18850 21750 26100 35960 48575 psi
Comment on the applicability of each of the Mohr-Coulomb, Griffith, and Hoek-Brown criteria for the
testing results.
A free-headed drilled shaft, shown in Figure 4, has an elastic modulus, Ep = 20,000 MPa.
M, = 880 kN m
Q = 245 kN,
Sand
at = 19 kN/m3
O' = 34°
1.2 m
Figure 4
(a) Determine the ground line deflection, x.
Chapter 19 Solutions
Fundamentals of Geotechnical Engineering (MindTap Course List)
Ch. 19 - Prob. 19.1PCh. 19 - Prob. 19.2PCh. 19 - Redo Problem 19.2. Use Eq. (19.4) and Es = 600 pa....Ch. 19 - For the drilled shaft described in Problem 19.2,...Ch. 19 - Prob. 19.5PCh. 19 - Prob. 19.6PCh. 19 - Prob. 19.7PCh. 19 - For the drilled shaft described in Problem 19.7,...Ch. 19 - For the drilled shaft described in Problem 19.7,...Ch. 19 - Prob. 19.10P
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