ATTERBERG LIMITS AND SIEVE ANALYSIS

Question 1

boundary between the solid and semi-solid state

Answer 1

Shrinkage Limit

Question 2

Boundary between the semi-solid and plastic state

Answer 2

Plastic Limit

Question 3

boundary between the plastic and liquid state

Answer 3

Liquid Limit

Question 4

plastic limit will be determined by rolling a soil paste into ____ diameter threads until it crumbles, and determining the moisture content.

Answer 4

3.2mm

Question 5

“Atterberg Limits” is named after

Answer 5

the Swedish scientist Albert Mauritz Atterberg

Question 6

Originally, six “limits of consistency” of fine-grained soils were defined by Albert Atterberg: the upper limit of viscous flow, the liquid limit, the sticky limit, the cohesion limit, the plastic limit, and the shrinkage limit. In current engineering usage, the term usually refers only to the liquid limit, plastic limit, and in some references, the shrinkage limit.

Answer 6

Atterberg Limits

Question 7

the relative ease with which a soil can be deformed.

Answer 7

Consistency

Question 8

the water content, in percent, of soil at the arbitrarily defined boundary between the semiliquid and plastic states.

Answer 8

Liquid Limit

Question 9

the water content, in percent, of soil at the boundary between the plastic and semi-solid states.

Answer 9

Plastic Limit

Question 10

a soil that has a range of water content over which it exhibits plasticity and which will retain its shape on drying.

Answer 10

Plastic Soil

Question 11

the range of water content over which a soil behaves plastically. Numerically, it is the difference between the liquid and plastic limits.

Answer 11

Plasticity Index

Question 12

Rotate the handle of the liquid limit device so that the cup lifts and drops at the rate of _______ drops per second.

Answer 12

1.9 to 2.1

Question 13

is the difference between the liquid and plastic limits.

Answer 13

Plasticity Index

Question 14

Roll the bass on the glass plate until it forms a thread about __ inches or ___mm in diameter.

Answer 14

⅛ inches or 3.2mm

Question 15

ASTM used for LL and PL

Answer 15

(ASTM D 4318 - Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils)

Question 16

The moisture content at which a standard cone of apex angle 30° and weight of 0.78 N (80 gf) will penetrate a distance d=20
mm in 5 seconds when allowed to drop from a position of point contact with the soil surface.

Answer 16

(BS 1377 - Fall Cone Method)

Question 17

The number of blows required to achieve closure
varies between ________. The results are plotted on semi-logarithmic graph paper.

Answer 17

15 and 35

Question 18

This method offers a more accurate method of determining the liquid and plastic limit;

Answer 18

Determination of Liquid Limit Using Fall Cone Method (BS 1377)

Question 19

The moisture content, in percent, at which the volume of the soil mass ceases to change. (ASTM D427/ ASTM D4943)

Answer 19

Shrinkage Limit

Question 20

What Soil Indices is indicated below?

0 - Non-plastic
1 – 5 Slightly plastic
5 – 10 Low plasticity
10 – 20 Medium plasticity
20 – 40 High plasticity
> 40 Very high plasticity

Answer 20

Plasticity Index Description

Question 21

defines the relative consistency of a cohesive soil in the natural state

Answer 21

Liquidity Index

Question 22

LI < 0 Semisolid
state

High strength; brittle; sudden
fracture is expected

0 < LI < 1 Plastic
state

Intermediate strength; soil
deformed like a plastic material

LI > 1 Liquid
state

Low strength; soil deforms like
a viscous fluid

Answer 22

TRUE

Question 23

the numerical difference between the plastic limit and shrinkage limit of the remolded soil

Answer 23

Shrinkage Limit

Question 24

• a valuable parameter for classifying the predominant minerals in the sediment

Answer 24

Activity of Clas; Ac

Question 25

• the ratio of a given volume change expressed as a percentage of dry volume to the corresponding charge
  in water content above the shrinkage limit expressed as a percentage of the weight of the oven-dried soil

Answer 25

Shrinkage Ratio

Question 26

AC = PI/μ

Where μ - percent finer than 0.002 mm

Answer 26

Activity of Clay

Question 27

Ac < 0.7 Inactive clay
0.7 < Ac < 1.2 Normal clay
Ac > 1.2 Active clay

Answer 27

TRUE

Question 28

an indicator of the relative shear strength. As ___ increases, the firmness, or shear strength of the soil
also increases.

Answer 28

Consistency Index

Question 29

the slope of the water content versus log10 of the blows number plot for the Casagrande cup method, is the
measure of the rate at which soil mass loses its shear strength with increased water content.

Answer 29

Flow Index

Question 30

is the determination of the size range of particles present in the soil, expressed as a percentage of the total
dry weight.

Answer 30

Mechanical Analysis

Question 31

Two methods are generally used to find the particle-size distribution of soil:

Answer 31

(1) sieve analysis
(2) hydrometer analysis

Question 32

—for particle sizes larger than 0.075 mm in diameter and

Answer 32

Sieve Analysis