Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Summer 8th Sem 2180609 Foundation Engineering Previous Question Paper

Enrolment No.___________

**GUJARAT TECHNOLOGICAL UNIVERSITY**

**BE - SEMESTER?VIII EXAMINATION ? SUMMER 2020**

Subject Code: 2180609

Subject Code: 2180609

**Date: 27/10/2020**

**Subject Name: Foundation Engineering**

**Time:**

**02.30 pm to 05.00 pm**

**Total Marks: 70**

**Instructions:**

**1. Attempt all questions.**

**2. Make suitable assumptions wherever necessary.**

**3. Figures to the right indicate full marks.**

**MARKS**

**Q.1 (a)**Define following terms;

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Bearing capacity, Ultimate bearing capacity, Safe bearing capacity

**(b)**Enlist the objectives of site exploration program.

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**(c)**Describe the standard penetration test used in soil exploration, with

**07**

neat diagram. Comment on the correction factor for N- values for the

dry sand and submerged fine sand.

**Q.2 (a)**What are the assumptions made in the derivation of Terzaghi's

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bearing capacity theory? Write the equation for the ultimate bearing

capacity.

**(b)**Explain the design criteria for satisfactory performance of

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foundation.

**(c)**Determine the net allowable load and gross allowable load for a

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square footing of 1.75m side and 1.25m deep. The soil below having;

=16kN/m3, c'=18 kN/m2 & ?'=25?. Take factor of safety =3 & use

Terzaghi's theory. The values of Nc'=14.8, Nq'=5.6, N'=3.2 for

?'=25?.

**OR**

**(c)**Enlist the factors affecting bearing capacity. Explain each factor in

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detail.

**Q.3 (a)**Describe limitations of plate load test.

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**(b)**Explain Feld's rule for the efficiency of pile grouped with 3, 4, 5 &

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6 piles.

**(c)**Draw neat sketch of gravity retaining wall with forces acting on it.

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Discuss various stability checks for gravity retaining wall.

**OR**

**Q.3 (a)**Differentiate between general shear failure and local shear failure

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with neat sketch.

**(b)**Differentiate between the end bearing pile and friction pile.

**04**

**(c)**Why drainage in backfill of retaining wall is provided? Explain

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different methods of providing drainage of retaining wall.

**Q.4 (a)**Discuss the characteristics of the expansive soils.

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**(b)**Enlist the factors influencing the selection of piles.

**04**

**(c)**A group of 9 piles, 9mlong is used as the foundation of column. The

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piles are 30cm in diameter with centre to centre spacing 90cm. the

subsoil consists of clay with unconfined compressive strength

170kN/m2. Estimate safe load. Take factor of safety = 3, = 0.55 &

Nc = 9.

**OR**

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**Q.4 (a)**Explain differential free swell test for identification of expansive

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soils.

**(b)**What is Negative skin friction? What is its effect on the pile?

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**(c)**A square concrete pile 30cm x 30cm is driven into homogeneous sand

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layer, (?=30?, =18 kN/m3) for a depth of 12 m. calculate the ultimate

load. Take K=1.3, =18?, Nq=29 & Critical depth = 15B.

**Q.5 (a)**Define geosynthetics. Enlist the major types of geosynthetics.

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**(b)**Write short note on bentonite slurry.

**04**

**(c)**Explain different functions of geosynthetics, with neat sketches.

**07**

**OR**

**Q.5 (a)**Explain different foundations systems of expansive soils.

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**(b)**What is retaining wall? In which situations it is necessary?

**04**

**(c)**Describe measures required for treatment of expansive soils.

**07**

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This post was last modified on 04 March 2021