Fundamentals of Geotechnical Engineering (MindTap Course List)
5th Edition
ISBN: 9781305635180
Author: Braja M. Das, Nagaratnam Sivakugan
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 9, Problem 9.1P
(a)
To determine
State whether the statement “During consolidation, effective stress decreases” is true or false.
(a)
Expert Solution
Answer to Problem 9.1P
The statement is False.
Explanation of Solution
Calculate the effective stress
Here,
Consolidation is the process to drain the water from the soil particle. The pore water pressure becomes zero during the consolidation. Hence, the total stress will increase due to zero pore water pressure.
Hence, the statement “During consolidation, effective stress decreases” is False.
(b)
To determine
State whether the statement “Compression index can be less or greater than the swelling index” is true or false.
(b)
Expert Solution
Answer to Problem 9.1P
The statement is False.
Explanation of Solution
Consider the Boston blue clay soil.
Refer to Table 9.2 “Compression and Swell of natural soils” in the Text Book.
Take the value of compression index
Take the value of swell index
The value of compression index
Hence, the statement “Compression index can be less or greater than the swelling index” is False.
(c)
To determine
State whether the statement “The larger the coefficient of consolidation, the faster is the consolidation process” is true or false.
(c)
Expert Solution
Answer to Problem 9.1P
The statement is True.
Explanation of Solution
“Coefficient of consolidation”
It is directly proportional to permeability, if the soil has high permeability then the “coefficient of consolidation” of the soil is high.
Hence, the statement “The larger the coefficient of consolidation, the faster is the consolidation process” is True.
(d)
To determine
State whether the statement “High plastic clays have higher
(d)
Expert Solution
Answer to Problem 9.1P
The statement is False.
Explanation of Solution
The “coefficient of consolidation” is less for high plastic clay due to the plastic limit, that is the expel of water from high plastic clay is not as much the low plastic clay.
Hence, the statement “High plastic clays have higher
(e)
To determine
State whether the statement “The stiffer clay, the lower is the coefficient of consolidation” is true or false.
(e)
Expert Solution
Answer to Problem 9.1P
The statement is False.
Explanation of Solution
The clay is stiff when the “coefficient of consolidation” is high and it is loose when the “coefficient of consolidation” is less.
Hence, the statement “The stiffer clay, the lower is the coefficient of consolidation” is False.
Want to see more full solutions like this?
Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
The following figure shows a vertical retaining wall with a granular backfill:
100.0
50.0
40.0
30.0
20.0
10.0-
5.0-
4.0
3.0-
2.0-
= +1 0.8 0.6
0.4
0.2
0.0
-0.2
-0.4
-0.6
-0.8
-0.9
1.0-
0
10
20
30
40
45
' (deg)
(a)
Figure Caquot and Kerisel's solution for K
3
Let H = 4m, a = 17.5°, y = 17.5 kN/m³, ' = 35°, and 8' = 10°. For given values of ' and 8', R' = 0.53. Based on Caquot and Kerisel's solution, what would be the passive force per meter length of the wall?
(Enter your answer to two significant figures.)
Pp=
kN/m
The dam presented below is 180 m long (in the direction perpendicular to the plane of thecross-section). For the water elevations given on the drawing:a) Construct the flow net (minimum number of equipotential lines should be 10),b) Calculate the rate of seepage for the entire dam,c) Find the total uplift force on the dam (ignore barriers), andd) Estimate the hydraulic gradient at points A, B, and D
The influence line for moment at B for the beam shown is
A
-6 m-
B
a. O at A, 6 at B, and 15 at C
b. 1 at A, 1 at B, and 1 at C
c. O at A, 0 at B, and -9 at C
d. O at A, 1 at B, and 1 and C
-9 m-
Chapter 9 Solutions
Fundamentals of Geotechnical Engineering (MindTap Course List)
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, civil-engineering and related others by exploring similar questions and additional content below.Similar questions
- Consider the following figure: H/3 Pa Given: H = 7 m, y = 13 kN/m³, ø′ = 25°, c′ = 12 kN/m², and a = 10°. For given values, K₁ = 0.296. Calculate the Rankine active force per unit length of the wall after the occurrence of the tensile crack. (Enter your answer to three significant figures.) Pa = kN/marrow_forwardWall movement to left 45+ '/2 45 + 6'/2 Rotation of wall about this point A vertical retaining wall shown in the figure above is 7 m high with a horizontal backfill. For the backfill, assume that y = 14.5 kN/m³, ' = 26°, and c′ = 18 kN/m². Determine the Rankine active force per unit length of the wall after the occurrence of the tensile crack. (Enter your answer to three significant figures.) Pa = kN/marrow_forwardConsider the following figure: 0.6 "d 0.5 k₁ = 0 0.4 03 =0 kh = 0.2 0.3 0.025 0.2 0.05 0.1 0.1 0.2 0 -0.1 ↓ 0 5 10 15 20 25 30 35 40 45 ' (deg) For a retaining wall with a vertical back and horizontal backfill with a c'-' soil, the following are given: H = 10 ft Y = 111 lb/ft³ ' = 25° kh = 0.2 k₁ = 0 c = 113 lb/ft² Determine the magnitude of active force Pae on the wall. (Enter your answer to two significant figures.) Pae = lb/ftarrow_forward
- A 13.0 ft high vertical wall retains an overconsolidated soil where OCR = 1.5, c' = 0, and ' magnitude and the location of the horizontal load on the wall, assuming the at-rest condition. Use Ysat (Enter your answers to three significant figures.) 33°. If the entire soil behind the wall is submerged with the water level at the ground surface, determine the 127 lb/ft³. Activity Frame P₁ = lb/ft Height above the bottom of the wall = O Icon Kov ftarrow_forward= A 5 m high smooth vertical wall retains a clay backfill with c = 13 kN/m², ' -25°, and y = 17.0 kN/m³. The clay is in active state. a. Determine the maximum tensile stress within the clay. (Enter your answer to three significant figures.) σα = kN/m² b. Determine the depth of the tensile cracks. (Enter your answer to three significant figures.) Zo = m c. Determine the magnitude and location of the active thrust, neglecting the tensile zone. (Enter your answers to three significant figures.) Pa x = = kN/m² marrow_forwardA composite beam is fabricated by bolting two 3.1-in.-wide by 14-in.-deep timber planks to the sides of a 0.4-in. by 14-in. steel plate. The moduli of elasticity of the timber and the steel are 1940 ksi and 30300 ksi, respectively. The simply supported beam spans a distance of 21 ft and carries two concentrated loads P, which are applied as shown. Assume LAB = LCD = 5 ft, Lgc = 11 ft, b = 3.1 in., d = 14 in. and t = 0.4 in. (a) Determine the maximum bending stresses σ,, σ, produced in the timber planks and the steel plate if P = 2.1 kips. (b) Assume that the allowable bending stresses of the timber and the steel are 830 psi and 24900 psi, respectively. Determine the largest acceptable magnitude for concentrated loads P. (You may neglect the weight of the beam in your calculations.) LAB B Answers: LCD LBC b Cross section D ksi, σ, = i ksi. (a) σ, = (b) P= i i kips.arrow_forward
- The internal shear force at a certain section of a steel beam is V = 107 kips. If the beam has the cross section shown, determine the shear stress at point H, which is located 2 in. below the top surface of the flanged shape. The centroid is 5.283 in. above the bottom surface of the beam, and the moment of inertia about the z axis is 465.8 in.4. 5 in. 2 in. H 业 1 in. 1 in. 12 in. 8 in. 1 in. 11.51 ksi O 9.72 ksi 8.34 ksi 6.03 ksi ○ 7.73 ksiarrow_forwardThe beam shown will be constructed from a standard steel W-shape using an allowable bending stress of 33.6 ksi. Assume P = 70 kips. L₁ = 2.2 ft, and L2 = 6.6 ft. (a) Determine the minimum section modulus required for this beam. (b) From the table below, select the lightest W shape that can be used for this beam. (c) What is the total weight of the steel beam itself (ie, not including the loads that are carried by the beam)? Lu B D L2 L₁ Wide-Flange Sections or W Shapes-U.S. Customary Units x x be Web Area Depth thickness Flange width Flange thickness Designation A d Tw by 4 S₁ و" in.² in. in. in. in. in,4 in.³ in. in.4 in,³ in. W24 x 94 27.7 24.3 0.515 9.07 0.875 2700 222 9.87 109 24.0 1.98 24 x 76 22.4 23.9 0.440 8.99 0.680 2100 176 9.69 82.5 18.4 1.92 24 x 68 20.1 23.7 0.415 8.97 0.585 1830 154 9.55 70.4 15.7 1.87 24 x 55 16.2 23.6 0.395 7.01 0.505 1350 114 9.11 29.1 8.30 1.34 W21 x 68 20.0 21.1 0.430 8.27 0.685 1480 140 8.60 64.7 15.7 1.80 21 x 62 18.3 21.0 0.400 8.24 0.615 1330 127…arrow_forwardA composite beam is made of two brass [E=114 GPa] bars bonded to two aluminum [E = 74 GPa] bars, as shown. The beam is subjected to a bending moment of 335 N-m acting about the z axis. Using a = 5 mm, b = 30 mm, c = 10 mm, and d = 20 mm, calculate (a) the maximum bending stress in the aluminum bars. (b) the maximum bending stress in the brass bars. N Aluminum C Brass Brass Aluminum b Answers: (a) σal= (b) Obr= a a MPa MPaarrow_forward
- A standard steel pipe (D = 3.500 in.; d = 3.068 in.) supports a concentrated load of P = 630 lb as shown. The span length of the cantilever beam is L = 4 ft. Determine the magnitude of the maximum horizontal shear stress in the pipe. 720 psi 761 psi 508 psi 564 psi 667 psi L Pipe cross section.arrow_forwardA beam is subjected to equal bending moments of M₂ = 59 kip-ft. The cross-sectional dimensions are b₁ = 7.5 in., d₁ = 1.4 in., b₂ = 0.55 in., d₂ = 5.0 in., b3 = 3.2 in., and d3 = 1.5 in. Determine: (a) the centroid location (measured with respect to the bottom of the cross-section), the moment of inertia about the z axis, and the controlling section modulus about the z axis. (b) the bending stress at point H. Tensile stress is positive, while compressive stress is negative. (c) the bending stress at point K. Tensile stress is positive, while compressive stress is negative. (d) the maximum bending stress produced in the cross section. Tensile stress is positive, while compressive stress is negative. M₂ Z M₂ Answer: (a) y= i Iz= in. in.4 S= i on,3 (b) σH= i ksi (c) OK = i ksi (d) σmax= ksi K b₁ d₁ H b₂ b3 d₂ d3arrow_forwardA cantilever timber beam with a span of L = 2.9 m supports a uniformly distributed load w. The beam width is b = 300 mm and the beam height is h = 160 mm. The allowable bending stress of the wood is 7 MPa. Determine the magnitude of the maximum load w that may be carried by the beam. Answer: w= I i kN/m.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Fundamentals of Geotechnical Engineering (MindTap...Civil EngineeringISBN:9781305635180Author:Braja M. Das, Nagaratnam SivakuganPublisher:Cengage Learning
Principles of Foundation Engineering (MindTap Cou...Civil EngineeringISBN:9781337705028Author:Braja M. Das, Nagaratnam SivakuganPublisher:Cengage Learning
Principles of Foundation Engineering (MindTap Cou...Civil EngineeringISBN:9781305081550Author:Braja M. DasPublisher:Cengage Learning
Principles of Geotechnical Engineering (MindTap C...Civil EngineeringISBN:9781305970939Author:Braja M. Das, Khaled SobhanPublisher:Cengage Learning
Construction Materials, Methods and Techniques (M...Civil EngineeringISBN:9781305086272Author:William P. Spence, Eva KultermannPublisher:Cengage Learning
Fundamentals of Geotechnical Engineering (MindTap...
Civil Engineering
ISBN:9781305635180
Author:Braja M. Das, Nagaratnam Sivakugan
Publisher:Cengage Learning
Principles of Foundation Engineering (MindTap Cou...
Civil Engineering
ISBN:9781337705028
Author:Braja M. Das, Nagaratnam Sivakugan
Publisher:Cengage Learning
Principles of Foundation Engineering (MindTap Cou...
Civil Engineering
ISBN:9781305081550
Author:Braja M. Das
Publisher:Cengage Learning
Principles of Geotechnical Engineering (MindTap C...
Civil Engineering
ISBN:9781305970939
Author:Braja M. Das, Khaled Sobhan
Publisher:Cengage Learning
Construction Materials, Methods and Techniques (M...
Civil Engineering
ISBN:9781305086272
Author:William P. Spence, Eva Kultermann
Publisher:Cengage Learning