Soil Mechanics and Foundation Engineering - Engineering

Q1:

260 g of wet soil was taken in a pycnometer jar of weight 400 g in order to find the moisture content in the soil, with specific gravity of soil particles 2.75. The weight of soil and remaining water filled in pycnometer without air bubbles was 1415 g and the weight of pycnometer filled with water alone was 1275 g. The moisture content in the soil is

A 24.2%

B 18.2%

C 53.8%

D none of these.

ANS:B - 18.2%

WATER CONTENT = ([{(W2 - W1)/(W3 - W4)}{(G-1)/G]-1)*100.

Where,

W1 = wt. of empty Pycnometer = 400 g.

W2 = wt. of the Pycnometer with wet soil = 260 + 400 = 660.

W3 = wt. of the Pycnometer and soil, filled with water = 1415.

W4 = wt. of Pycnometer filled with water only = 1275.

G = Specific gravity of solids = 2.75.

Water content = ([(660 - 400)/(1415 - 1275)][(2.75 - 1)/(2.75)] - 1)*100.

= [(260/140)(1.75/2.75) - 1]*100 = 18.18% answer. Gs = {(260/140)*((2.75-1)/2.75 )}-1.

Gs = 1.857*(.636)-1.

Gs = .181 = 18.1%.