Download GTU BE/B.Tech 2019 Summer 8th Sem New 2180609 Foundation Engineering Question Paper

FirstRanker.com

Subject Code: 2180609

GUJARAT TECHNOLOGICAL UNIVERSITY

--- Content provided by‍ FirstRanker.com ---

Instructions:

1. Attempt all questions.

--- Content provided by FirstRanker.com ---

2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.

Q.1 (a) Answer the following. [03]

1. Define: ultimate bearing capacity of soil mass.
2. What is a significant depth?

--- Content provided by‍ FirstRanker.com ---

3. As the cohesion decreases, adhesion increases. (True/False)

(b) Give the classification of shallow foundations and deep foundations. [04]

(c) Determine the gross safe load that can be carried out by a square footing of size 2.2 m x 2.2 m, placed at a depth of 1.6 m below ground level. The water table is at a great depth. Foundation soil has the properties: ?d =16.5 kN/m³, f = 20°, N¢'=11.8, Ng' = 3.8, Ni' = 1.3. C = 11 kN/m². Assume F.S. =2.5. [07]

Q.2 (a) What is the effect of increase in width of a footing on bearing capacity of a footing resting on (a) sand and (b) clay? [03]

(b) What are the engineering tests usually conducted to assess the swelling potential of an expansive soil. Discuss any one of them. [04]

--- Content provided by‌ FirstRanker.com ---

(c) What are the objectives of a soil investigation program? List the various methods of soil investigation. What is a bore log? [07]

OR

(c) Differentiate between flexible pavement and rigid pavement. Describe briefly the various methods for design of flexible pavement. [07]

Q.3 (a) What are the limitations of dynamic pile load formulas? [03]

(b) Determine the area ratio for the following soil samplers and comment on the nature of the samples obtained. [04]

--- Content provided by​ FirstRanker.com ---

1. Core cutter : 165 mm outer diameter, 150 mm inner diameter.
2. Seamless tube (Shelby) : 51 mm outer diameter, 48 mm inner diameter.

(c) Explain the Skempton's-analysis for a clayey soil in detail. [07]

OR

Q.3 (a) What are the different circumstances under which a pile foundation is used? [03]

--- Content provided by⁠ FirstRanker.com ---

(b) Comment on the following statements: [04]

1. Settlement of a group of vertical piles is usually more than that of a single pile under equal axial load.
2. The principal effect of negative skin friction is to reduce factor of safety.

(c) Write step by step procedure to perform standard penetration test in the field. How it differs from plate load test? [07]

Q.4 (a) Explain the functions of (i) Batter pile (ii) Fender pile. [03]

--- Content provided by​ FirstRanker.com ---

(b) Write assumptions made in the Terzaghi's theory of bearing capacity. [04]

(c) A square pile group of 9 piles was driven in to soft clay extending to a large depth. The diameter and length of the piles were 30 cm and 9 m respectively. If the unconfined compressive strength of clay is 90 kN/m² and pile spacing is 90 cm centre to centre, what is the capacity of the group? Assume F.S. = 2.5 and adhesion factor a = 0.75. [07]

OR

Q.4 (a) Which are the various parameters used for identification of expansive soil? [03]

(c) What do you understand by contact pressure? On which factors it depends? Draw contact pressure distribution diagram for flexible and rigid footings on sand and clayey soil. [07]

--- Content provided by‍ FirstRanker.com ---

Q.5 (a) Explain the importance of drainage for backfill in retaining wall [03]

(b) Classify the geosynthetic materials and explain any two of them. [04]

(c) What is the ‘active zone’ in black cotton soil? Explain the properties of black cotton soil. [07]

OR

Q.5 (a) What are the field conditions that generally favours swelling in an expansive soil? [03]

--- Content provided by​ FirstRanker.com ---

(b) Draw an under reamed pile with detailed configuration. [04]

(c) Discuss the requirements which must be satisfied for the safe design of a retaining wall. [07]

FirstRanker.com