Concept explainers
Figure 16.21 shows a continuous foundation with a width of 1.8 m constructed at a depth of 1.2 m in a granular soil. The footing is subjected to an eccentrically inclined loading with e = 0.3 m, and α = 10°. Determine the gross ultimate load, Qu(ei), that the footing can support using:
- a. Meyerhof (1963) method [Eq. (16.52)]
- b. Saran and Agarwal (1991) method [Eq. (16.53)]
- c. Patra et al. (2012) reduction factor method [Eq. (16.54)]
(a)
The gross ultimate load
Answer to Problem 16.19P
The gross ultimate load
Explanation of Solution
Given information:
The unit weight of the soil
The value of cohesion
The soil friction angle
The location of depth of footing base
The width of the footing B is 1.8 m.
The value of eccentricity e is 0.3 m.
The inclined angle
Calculation:
Determine the effective width of the footing using the relation.
Substitute 1.8 m for B and 0.3 for e.
For the continuous foundation, all shape factors are equal to one
Determine the depth factor
Substitute 1.2 m for
Determine the depth factor
Substitute
Determine the inclination factor
Substitute
Determine the inclination factor
Substitute
Determine the ultimate bearing capacity of the soil
Here,
Refer Table 16.2, “Bearing-capacity factors
For
The values of
Substitute 0 for
Determine the gross ultimate load
Substitute
Therefore, the gross ultimate load
(b)
The gross ultimate load
Answer to Problem 16.19P
The gross ultimate load
Explanation of Solution
Given information:
The unit weight of the soil
The value of cohesion
The soil friction angle
The location of depth of footing base
The width of the footing B is 1.8 m.
The value of eccentricity e is 0.3 m.
The inclined angle
Calculation:
Determine the ratio of
Substitute 0.3 for e and 1.8 m for B.
Determine the gross ultimate load
Here,
Refer Figure 16.14, “Variation of
Take the
Refer Figure 16.15, “Variation of
Take the
Refer Figure 16.16, “Variation of
Take the
Substitute 0 for
Therefore, the gross ultimate load
(c)
The gross ultimate load
Answer to Problem 16.19P
The gross ultimate load
Explanation of Solution
Given information:
The unit weight of the soil
The value of cohesion
The soil friction angle
The location of depth of footing base
The width of the footing B is 1.8 m.
The value of eccentricity e is 0.3 m.
The inclined angle
Calculation:
For the continuous foundation, all shape factors are equal to one
Determine the depth factor
Substitute 1.2 m for
Determine the depth factor
Substitute
Determine the ultimate bearing capacity of the soil
Refer Table 16.2, “Bearing-capacity factors
Take the
Substitute 0 for
Determine the gross ultimate load
Substitute 1.8 m for B,
Therefore, the gross ultimate load
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Chapter 16 Solutions
MindTap Engineering for Das/Sobhan's Principles of Geotechnical Engineering, SI Edition, 9th Edition, [Instant Access], 2 terms (12 months)
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