Question 12.16: Refer to Figure 12.22. The mat has dimensions of 90 ft × 120...

Introduction to Geotechnical Engineering

Refer to Figure 12.22. The mat has dimensions of 90 ft × 120 ft, and the live load and dead load on the mat are 45 × 10³ kip. The mat is placed over a layer of soft clay that has a unit weight of 120 lb/ft³. Find $D_f$ for a fully compensated foundation.

12.22

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Question: 12.6

A square foundation is shown in Figure 12.9. Assume that the load eccentricity e = 0.5 ft. Determine the ultimate load, Qult. ...

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With c′ = 0, Eq. 12.20 becomes

q_u^\prime =...

Question: 12.5

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From Eq. (12.17), eccentricity

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Question: 12.4

A continuous foundation is shown in Figure 12.7. If the load eccentricity is 0.5 ft, determine the ultimate load, Qult, per unit length of the foundation. ...

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With c′ = 0, Eq. (12.20) gives

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Question: 12.1

Consider a shallow foundation with the following: ● Foundation: B = 3 ft L = 5 ft Df = 3 ft ● Soil: γ = 110 lb/ft³ φ′ = 25° c′ = 400 lb/ft² Determine the gross allowable load the foundation can carry. Use FS = 4. ...

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From Eq. (12.7), noting that

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Question: 12.3

A square column foundation to be constructed on a sandy soil has to carry a gross allowable inclined load of 59.6 kip. The depth of the foundation will be 2.3 ft. The load will be inclined at an angle of 20° to the vertical (Figure 12.5). Assume that the unit weight of the soil is 114.5 lb/ft³. ...

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Question: 12.2

A 2.0 m wide strip foundation carries a wall load of 350 kN/m in a soil where γ = 19.0 kN/m³, c′ = 5 kN/m² and φ′ = 23°. The foundation depth is 1.5 m. Determine the factor of safety of this foundation. ...

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For φ′ = 23° from Table 12.1, φ′

N_c[/l...

Question: 12.7

A rigid shallow foundation 3 ft × 6 ft is shown in Figure 12.15. Calculate the elastic settlement at the center of the foundation. ...

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\bar...

Question: 12.17

Refer to Example 12.16. For the clay, cu = 270 lb/ft². If the required factor of safety against bearing capacity failure is 3, determine the depth of the foundation. ...

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From Eq. (12.58), we have FS

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Question: 12.15

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From Eq. (12.43),

F_d =1+0.33(D_f/B)=1+0.33...

Question: 12.14

Determine the net allowable bearing capacity of a 10 m × 15 m raft foundation resting on a clay where cu = 80 kN/m² and Df = 3 m. Allow a factor of safety of 3. ...

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From Eq. (12.54),

q_{all(net)}=1.713 c_u\le...