A person who cannot blame himself does not blame anyone. Looking through the lens of infinity is more terrifying than anything. Where am I and where is all that pettiness! Amim: full-general Teri Teri flooded From bite to evening prayer Dangal: Vast Inference: investigation, interrogation Vomiting: Vomiting Kefal: Serin Qalchmaq: Strong Tallow: Fat Zanjmore: Crying and wailing Beginning of page 20 of wall 485 When one has lost the illusion of eternity, it doesn't matter how many hours or how many years you wait. Wall p. 25 It was strange to me that even though he was alive, he let his hair cover his face. Wall p. 32 Tipa tap with the tip of the toe

1. Classification of Soil
1
Baghlan university

2. Outline
• Soil Classification Systems
• USDA Textural Classification System
• AASHTO Classification System
• Unified Soil Classification System
• Comparison between the AASHTO and Unified Systems
2
Baghlan university

3. Unified Soil Classification System
• The original form of this system was proposed by Casagrande
in 1942 for use in the airfield construction works undertaken
by the Army Corps of Engineers during World War II.
• Widely by engineers (ASTM Test Designation D-2487).
• This system classifies soils into two broad categories:
1. Coarse-grained soils
2. Fine-grained soils
3
Baghlan juniversity

4. Unified Soil Classification System
• Coarse-grained soils that are gravelly and sandy in nature with
less than 50% passing through the No. 200 sieve. The group
symbols start with a prefix of G or S. G stands for gravel or
gravelly soil, and S for sand or sandy soil.
• Fine-grained soils are with 50% or more passing through the
No. 200 sieve. The group symbols start with prefixes of M,
which stands for inorganic silt, C for inorganic clay, or O for
organic silts and clays. The symbol Pt is used for peat, muck,
and other highly organic soils.
4
Baghlan university

5. Unified Soil Classification System
5
Baghlan university

6. Plasticity Chart
6
Baghlan university

7. Unified Soil Classification System
• Information needed:
1. Percent of gravel—that is, the fraction passing the 76.2-mm sieve
and retained on the No. 4 sieve (4.75-mm opening)
2. Percent of sand—that is, the fraction passing the No. 4 sieve
(4.75-mm opening) and retained on the No. 200 sieve (0.075-mm
opening)
3. Percent of silt and clay—that is, the fraction finer than the No.
200 sieve (0.075-mm opening)
4. Uniformity coefficient (Cu) and the coefficient of gradation (Cc)
5. Liquid limit and plasticity index of the portion of soil passing the
No. 40 sieve
7
Baghlan university

8. Unified Soil Classification System
1. Fine fraction = percent passing No. 200 sieve
2. Coarse fraction = percent retained on No. 200 sieve
3. Gravel fraction = percent retained on No. 4 sieve
4. Sand fraction = (percent retained on No. 200 sieve) 2 (percent
retained on No. 4 sieve)
8
Baghlan university

9. Unified Soil Classification System
9
Alberoni University, Spring 2019

10. Unified Soil Classification System
1
Baghlan un iversity

11. Comparison between the AASHTO
and Unified Systems
• Both soil classification systems, AASHTO and Unified, are
based on the texture and plasticity of soil.
• Also, both systems divide the soils into two major categories,
coarse grained and fine grained, as separated by the No. 200
sieve.
• According to the AASHTO system, a soil is considered fine
grained when more than 35% passes through the No. 200
sieve. According to the Unified system, a soil is considered
fine grained when more than 50% passes through the No. 200
sieve.
• In the AASHTO system, the No. 10 sieve is used to separate
gravel from sand; in the Unified system, the No. 4 sieve is
used.
1
Alberoni University, Spring 2019

12. Unified Soil Classification System
• Both soil classification systems, AASHTO and Unified, are
based on the texture and plasticity of soil.
• Also, both systems divide the soils into two major categories,
coarse grained and fine grained, as separated by the No. 200
sieve.
• According to the AASHTO system, a soil is considered fine
grained when more than 35% passes through the No. 200
sieve. According to the Unified system, a soil is considered
fine grained when more than 50% passes through the No. 200
sieve.
• In the AASHTO system, the No. 10 sieve is used to separate
gravel from sand; in the Unified system, the No. 4 sieve is
used.
1
Alberoni University, Spring 2019

13. Comparison between the AASHTO
and Unified Systems
Example 5.4:
• The results of the particle-size analysis of a soil are as follows:
• Percent passing through the No. 10 sieve = 100
• Percent passing through the No. 40 sieve = 80
• Percent passing through the No. 200 sieve = 58
• The liquid limit and plasticity index of the minus No. 40
fraction of the soil are 30 and 10, respectively. Classify the soil
by the Unified classification system.
1
Baghlan university

14. Comparison between the AASHTO
and Unified Systems
Example 5.6:
• For a given soil, the following are known:
• Percent passing through No. 4 sieve = 70
• Percent passing through No. 200 sieve = 30
• Liquid limit = 33
• Plastic limit = 12
• Classify the soil using the Unified Soil Classification System.
Give the group symbol and the group name.
1
Bahglan university

15. Comparison between the AASHTO
and Unified Systems
• Both soil classification systems, AASHTO and Unified, are
based on the texture and plasticity of soil.
• Also, both systems divide the soils into two major categories,
coarse grained and fine grained, as separated by the No. 200
sieve.
• According to the AASHTO system, a soil is considered fine
grained when more than 35% passes through the No. 200
sieve. According to the Unified system, a soil is considered
fine grained when more than 50% passes through the No. 200
sieve.
• In the AASHTO system, the No. 10 sieve is used to separate
gravel from sand; in the Unified system, the No. 4 sieve is
used.
1
Baghlan university

16. Question?
1
Baghlan university