Exam 1 - Lecture 4

Front 1

Soil Classification Systems

Back 1

- Unified Soil Classification System (USCS)

- AASHTO

- US Department of Agriculture

- Others

Front 2

Sieve Analysis

Back 2

Determine grain size distribution

Limit is No. 200 sieve (0.075 mm)

Front 3

Hydrometer Analysis

Back 3

Determine grain size distribution

For soil passing through No. 200 sieve (0.075 mm)

Front 4

D10

Back 4

"Effective Size"

Diameter with 10% of the sample is finer

Front 5

Well-graded

Back 5

A good share of particle sizes over a wide range

Front 6

Poorly-graded

Back 6

Too many/not enough particles of certain sizes

Front 7

Uniform

Back 7

Almost all particles are the same size

Front 8

Gap graded

Back 8

Larger and smaller particles present, medium sizes missing

Front 9

To determine if well-graded

Back 9

Sands:

Cu > 6 and 1 < Cc < 3

GRavel:

Cu > 4 and 1 < Cc < 3

Front 10

Atterberg Limits

Back 10

To determine plasticity of finer soil (-No. 40 sieve)

Front 11

Liquid Limit

Back 11

Water content at which the soil behaves like a liquid

Front 12

Plastic Limit

Back 12

Water content at which the soil changes from a semi-solid to plastic state

Front 13

Shrinkage Limit

Back 13

Water content at which the soil changes from a solid to semisolid state

Front 14

Plasticity Index

Back 14

Range of water contents where the soil is plastic (moldable)

Front 15

Liquidity Index

Back 15

Indication of the consitency of soil in its natual state

Front 16

Activity

Back 16

Index of clay mineral type - correlated to behavior like shrink/swell