SREE VIDYANIKETHAN ENGINEERING COLLEGE

III B.Tech. I Semester Civil Engineering

Soil Mechanics

ASSIGNMENT TEST I

Academic Year 2015-16

1. (a) Explain various types of soil structures with neat sketches.(b) A fully saturated soil sample was extracted during an oil well drilling. The wet mass of the sample was 3.15 kg and the volume of the sampling tube was 0.001664 m3. After analysis the soil sample was found to contain 28.2% of the liquid as kerosene and the dry mass as 2.67kg. The specific gravity of soil grains was 2.68. Determine the bulk density, void ratio and water content of the sample.

2. (a) Define the following terms: Void ratio, Porosity, Degree of Saturation, Percentage air voids, Air content and Water content.(b) Show that Se = wG

3. For constructing an embankment, the soil is transported from a borrow area using a truck which can carry 6 m3 of soil at a time. With the following details, determine the number of truck loads of soil required to obtain 100 m3 of compacted earth fill and the volume of borrow pit.

PropertyBorrow area (In-situ)Truck

(Loose)Field (Compacted)

Bulk Unity Weight (kN/m3)16.611.518.2

Water Content (%)8614

4. (a) Define and explain: Sensitivity; Thixotrophy and Activity of soils.(b) The Atterberg limits of a clay are, liquid limit = 60%, plastic limit = 45% and natural moisture content = 50%. Determine i) liquidity index ii) consistency index iii) plasticity index.

5. (a) With the help of sketches explain the following:

i. well graded soil,

ii. uniformly graded soil,

iii. gap graded soil.

(b) The Atterberg limits of a soil sample are: liquid limit = 50%, plastic limit = 30% and shrinkage limit = 15%. If the specimen of this soil shrinks from a volume of 10 cm3 at liquid limit to 5.94 cm3 when oven dried, calculate the shrinkage ratio and specific gravity of soil solids.