Indira Gandhi National Open University (IGNOU) 2005 B.Tech Water Resource Engineering Foundation Engineering - Question Paper

Test Papers / Previous ques. Papers of IGNOU ET501 (B) Foundation Engineering December 2005
B.Tech. Civil (Construction Management)
Term-End exam

December, 2005

ET-501(B): FOUNDATION ENGINEERING

Time: three hours
Maximum Marks: 70

Note : ans any 5 ques.. All ques. carry equal marks. Use of calculator is allowed.
1. ans any 4 of the following: (4x10=40)

(a) explain the various methods of site exploration by boring.


(b) Briefly desctibe the subsequent :


(i) Depth of exploration
(ii) Recovery ratios
(iii) Modes of failures in shallow foundation
(v) Ultimate bearing capacity

(c) Determine the net ultimate bearing capacity for a square foundation shown in the figure beneath. The water table is located well beneath the base. Use Terzaghi's bearing capacity factors.

DIAGRAM

Soil properties
? = 18 kN/m3
c' = 16 kN/m2
p' = 300
Dr = 900 (dense)
(Nc = 37.2, Nq = 22.5, N? = 19.7)

(d) The foundation for a circular tank is to be of diameler 18 m and founded at a depth of 2.5 m.

The soil properties are :

c' = 0, p' = 340, ?= 19 kN/m3.

Determine the ultimate bearing capacity when the ground water is

(i) 2-0 m beneath foundation
(ii) at the base of the foundation, and
(iii) at 1.0 m beneath ground surface.

Use correction factors to consider the effect of water table. Use Terzaghi's formula. ( Nq = 36.5 , N? = 35.0 )

(e) 2 columns are loaded as shown in the figure beneath. Determine the dimensions of the rectangular combined footing to carry the column loads.

DIAGRAM

Size of column A is 45 x 45 cm and of column B is 50 x 50 cm, Allowable soil pressure is 300 kPa.

(f) explain the factors affecting the bearing capacity of soil.

2. ans any 3 of the following: (3x10=30)

(a) discuss the methods of controlling settlement.

(b) A retaining wall eight m high with a smooth veriical back retains a 2 layer dry cohesionless backfill with the subsequent properties :

0-4 m depth c= 0, p = 300. ? = 17 kN/m3 4-8 m depth c= 0, p = 340, ?= 20 kN/m3
Determine the total lateral earth force acting on the wall and its line of action.

(c) A load of 2000 kN is being taken by a square column footing. Side of the column is three m, footing rests on a silty soil with a Poisson's ratio = 0 3. Modulus of elasticity of the soil is 50 MPa. obtain the settlement at the centre and at the edge of the fooilng. presume influence factor for centre = 1.12 and at edge = 0.56.

Briefly define the kinds of piles based on the kind of materials used to construct them.

Enumerate the methods for determining the dynamic properties of soil. define the Seismic cone Penetration Test.

Earning:   Approval pending.