AT56 - Soil

Question 1

The top layer of the earth’s surface, consisting of disintegrated rock and decayed organic matter suitable for the growth of plant life.

Answer 1

SOIL

Question 2

The fertile surface layer of soil, as distinct from the subsoil.

Answer 2

TOPSOIL

Question 3

The bed or layer of earth immediately beneath the surface soil.

Answer 3

SUBSOIL

Question 4

The unbroken, solid rock that underlies all unconsolidated material on the earth’s surface, such as soil, clay, sand, or rock fragments.

Answer 4

BEDROCK

Question 5

Perennially frozen subsoil in arctic or subarctic regions. Also called pergelisol.

Answer 5

PERMAFROST

Question 6

Perennially frozen subsoil in arctic or subarctic regions. Also called permafrost.

Answer 6

PERGELISOL

Question 7

Soil containing a large amount of organic matter, usually very compressible and having poor load-sustaining properties.

Answer 7

ORGANIC SOIL

Question 8

A diagram of a vertical section of soil from the ground surface to the underlying material, showing a succession of horizons developed by weathering, deposition, or both.

Answer 8

SOIL PROFILE

Question 9

Any of a series of relatively distinct layers of soil or its underlying material found in a vertical section of land.

Answer 9

HORIZON

Question 10

A single bed or layer of sedimentary earth or rock having the same composition throughout, lying between beds of another kind.

Answer 10

STRATUM

Question 11

A process for determining the particle-size distribution in an aggregate, soil, or sediment.

Answer 11

SOIL ANALYSIS

Question 12

A numerical classification of soil by texture, used by the U.S. Department of Agriculture: (1) gravel, (2) sand, (3) clay, (4) loam, (5) loam with some sand, (6) silt-loam, and (7) clay-loam.

Answer 12

SOIL CLASS

Question 13

Seven classes of soil by texture as used by the U.S. Department of Agriculture.

Answer 13

GRAVEL, SAND, CLAY, LOAM, LOAM WITH SOME SAND, SILT-LOAM, and CLAY-LOAM

Question 14

A large, naturally rounded rock, lying on the surface of the ground or partially embedded in it.

Answer 14

BOULDER

Question 15

A naturally rounded stone, smaller than a boulder and larger than a pebble, used for rough paving, walls, and foundations.

Answer 15

COBBLE or COBBLESTONE

Question 16

Small pebbles and stones, or a mixture of this with sand, formed either naturally or by crushing rock, especially such material that will pass a 76-millimeter (or 3-inch) sieve and be retained on a No. 4 or 4.8-millimeter sieve.

Answer 16

GRAVEL

Question 17

Gravel having one or more fractured faces produced by mechanical crushing.

Answer 17

CRUSHED GRAVEL

Question 18

Stone having well-defined edges produced by the mechanical crushing of rocks or boulders.

Answer 18

CRUSHED STONE or CRUSHED ROCK

Question 19

A small-diameter, natural gravel, usually 6.4 millimeters to 9.5 millimeters (or 1/4 inch to 3/8 inch) in size, screened to specification.

Answer 19

PEA GRAVEL

Question 20

A small, rounded stone, especially one worn smooth by the action of water.

Answer 20

PEBBLE

Question 21

A loose, granular material resulting from the disintegration of rocks, consisting of grains smaller than gravel but coarser than silt.

Answer 21

SAND

Question 22

A well-graded, naturally occurring sand often used as a base or subbase material, having about 10% clay or just enough to make the mixture bind tightly when compacted.

Answer 22

SAND CLAY

Question 23

Loose sedimentary material consisting of fine mineral particles between 0.002 millimeters and 0.05 millimeters in diameter.

Answer 23

SILT

Question 24

A natural, earthy material that is plastic when moist but hard when fired and is used for making brick, tile, and pottery, composed mainly of fine particles of hydrous aluminum silicates less than 0.002 millimeters in diameter.

Answer 24

CLAY

Question 25

Soil containing 27% to 40% clay and 20% to 45% sand.

Answer 25

CLAY LOAM

Question 26

A clay formed by the decomposition of volcanic ash, having the ability to absorb large amounts of water and to expand to several times its natural volume.

Answer 26

BENTONITE

Question 27

A rich soil containing a relatively equal mixture of sand and silt and a smaller proportion of clay and organic matter.

Answer 27

LOAM

Question 28

An unstratified, cohesive, loamy deposit deposited by wind.

Answer 28

LOESS

Question 29

Of or pertaining to the practical applications of geological science in civil engineering.

Answer 29

GEOTECHNICAL

Question 30

The investigation and classification of a foundation soil based on observation and tests of material disclosed by borings or excavations to obtain the information necessary for the design of a foundation system.

Answer 30

FOUNDATION INVESTIGATION or SUBSURFACE INVESTIGATION

Question 31

Six technical data necessary for the design of a foundation system, derived during foundation investigation based observations and tests of materials disclosed by borings or excavations performed on foundation soil.

Answer 31

SHEARING STRENGTH, COMPRESSIBILITY, COHESION, EXPANSIVENESS, PERMEABILITY & MOISTURE CONTENT OF SOIL, ELEVATION OF WATER TABLE, AND ANTICIPATED & DIFFERENTIAL SETTLEMENT.

Question 32

The branch of civil engineering that deals with the mechanical behavior of soil when compressed or sheared, or when water flows through it.

Answer 32

SOIL MECHANICS

Question 33

The arrangement and aggregation of soil particles in a soil mass.

Answer 33

SOIL STRUCTURE

Question 34

An undisturbed, cylindrical sample of earth or rock obtained by means of a core drill and used for analysis and testing of bearing capacity. Also called boring.

Answer 34

CORE

Question 35

An undisturbed, cylindrical sample of earth or rock obtained by means of a core drill and used for analysis and testing of bearing capacity. Also called core.

Answer 35

BORING

Question 36

The levels of water content defining the boundaries between the different states of consistency of a plastic or cohesive soil, as determined by standard tests.

Answer 36

ATTERBERG LIMITS

Question 37

The numerical difference between the liquid limit and the plastic limit of a soil.

Answer 37

PLASTICITY INDEX

Question 38

The water content, expressed as a percentage of dry weight, at which a soil passes from a plastic to a liquid state.

Answer 38

LIQUID LIMIT

Question 39

The water content, expressed as a percentage of dry weight, at which a soil loses its plasticity and begins to behave as a solid.

Answer 39

PLASTIC LIMIT

Question 40

A soil that can be rolled into threads 3.2 millimeters (or 1/8 inch) in diameter without crumbling.

Answer 40

PLASTIC SOIL

Question 41

The water content, expressed as a percentage of dry weight, at which a reduction in water content will not cause a further decrease in the volume of a soil mass.

Answer 41

SHRINKAGE LIMIT

Question 42

Any gravel, sand, or silt that exhibits no cohensiveness or plasticity.

Answer 42

GRANULAR MATERIAL

Question 43

The property of a porous material that allows a gas or liquid to pass through its pore spaces.

Answer 43

PERMEABILITY

Question 44

The ratio of the volume of void spaces to the volume of solid particles in a soil mass.

Answer 44

VOID RATIO

Question 45

The void ratio corresponding to the critical density of a soil mass.

Answer 45

CRITICAL VOID RATIO

Question 46

The unit weight of a saturated granular material above which it will gain strength and below which it will lose strength when subjected to rapid deformation.

Answer 46

CRITICAL DENSITY

Question 47

Any permeable soil that allows the relatively free movement of water.

Answer 47

PERVIOUS SOIL

Question 48

Any fine-grained soil, such as clay, having pores too small to permit water to pass except by slow capillary action.

Answer 48

IMPERVIOUS SOIL

Question 49

Soil that has considerable strength when unconfined and air-dried, and significant cohesion when submerged.

Answer 49

COHESIVE SOIL

Question 50

Soil that has little or no strength when unconfined and air-dried, and litter or no cohesion when submerged.

Answer 50

COHESIONLESS SOIL

Question 51

The consolidation of sediment by the weight of overlying deposits, or a similar compression of soil, aggregate, or cementitious material by rolling, tamping, or soaking.

Answer 51

COMPACTION

Question 52

The water content of a soil at which maximum density can be attained through compaction.

Answer 52

OPTIMUM MOISTURE CONTENT

Question 53

A test for measuring the density of granular soils and the consistency of some clays at the bottom of a borehole, recording the number of blows required by a hammer to advance a standard soil sampler.

Answer 53

PENETRATION TEST

Question 54

The unit load required to produce a specified penetration into a soil at a specified rate of penetration.

Answer 54

PENETRATION RESISTANCE

Question 55

The property of a soil that enables its particles to resist displacement with respect to one another when an external force is applied, due largerly to the combined effects of cohesion and internal friction.

Answer 55

SHEARING STRENGTH or SHEARING RESISTANCE