Soil Mechanics Homework #1

Mr.Sirichai Srikwamcharoen( ศิ�ริ�ชั�ย ศิริ�ความเจริ�ญ)ID : 5322771312

Homeworks#11.1

US Siev

e No.

Mass of soil

retained on each

sieve (g)

Percent

retainedon

eachsieve (%)

Cumulative

percentretained on each

sieve (%)

Percent

finer (%)

4 0 0 0 10010 21.6 4.8 4.8 95.220 49.5 11 15.8 84.240 102.6 22.8 38.6 61.460 89.1 19.8 58.4 41.6100 95.6 21.24 79.64 20.3

6200 60.4 13.42 93.06 6.94Pan 31.2 6.93 99.99 0.01

450

Percent of soil retained = Mass of soil retainedTotal massof soil × 100

Percent finer = 100 – Percent of soil retained

U.S Sieve Series and Tyler Equivalents

http://www.buyactivatedcharcoal.com/sieve_size_chart

D10 = 0.09

D30 = 0.2

D60 = 0.41

Calculate the uniformity coefficient ( Cu )

Cu = D60D10 = 0.41mm0.09mm

= 4.6

Calculate the coefficient of gradation ( C c¿

C c = (D30×D30)(D10×D60)

= 0.2mm×0.2mm0.09mm×0.41mm

= 0.04mm2

0.0369mm2 = 1.08