Lare Section 2

Front 1

friable soil

Back 1

rocks or soil are easily broken into very small pieces or into powder

Front 2

plastic soil

Back 2

get deformed without rupture/breaking under external force

Front 3

plastic limit

Back 3

the moisture content at which a soil will just begin to crumble when rolled into a thread ⅛ in.

Front 4

shrinkage limit

Back 4

is the water content where further loss of moisture will not result in any more volume reduction

Front 5

liquid limit

Back 5

the moisture content at which soil begins to behave as a liquid material and begins to flow

Front 6

loose soil

Back 6

allows roots to penetrate easily. ... It also allows roots to penetrate the soil easily to reach for moisture and nutrients and build a strong support system for the plant. Soil that is compacted or heavy with clay and silt particles often needs amending to loosen the soil and prepare it for planting.

Front 7

gap graded soil

Back 7

a poorly graded soil that intermediate sizes are essentially absent from the gradation curve.

Front 8

well graded soil

Back 8

a soil that contains particles of a wide range of sizes and has a good representation of all sizes from the No. 4 to No. 200 sieves

Front 9

poor graded soil

Back 9

a soil that does not have a good representation of all sizes of particles from the No. 4 to No. 200 sieve

Front 10

uniform graded soil

Back 10

soil grains are identical in size

Front 11

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

Back 11

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

Front 12

SOIL

Back 12

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

Front 13

TOPSOIL

Back 13

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

Front 14

SOIL CLASS

Back 14

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.

Front 15

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

Back 15

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

Front 16

GRAVEL

Back 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.

Front 17

CRUSHED GRAVEL

Back 17

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

Front 18

CRUSHED STONE or CRUSHED ROCK

Back 18

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

Front 19

PEA GRAVEL

Back 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.

Front 20

PEBBLE

Back 20

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

Front 21

SAND

Back 21

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

Front 22

SAND CLAY

Back 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.

Front 23

SILT

Back 23

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

Front 24

CLAY

Back 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.

Front 25

CLAY LOAM

Back 25

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

Front 26

LOAM

Back 26

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

Front 27

LOESS

Back 27

An unstratified, cohesive, loamy deposit deposited by wind.

Front 28

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

Back 28

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.

Front 29

ATTERBERG LIMITS

Back 29

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.

Front 30

PLASTICITY INDEX

Back 30

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

Front 31

LIQUID LIMIT

Back 31

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

Front 32

PLASTIC LIMIT

Back 32

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

Front 33

PLASTIC SOIL

Back 33

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

Front 34

SHRINKAGE LIMIT

Back 34

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.

Front 35

GRANULAR MATERIAL

Back 35

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

Front 36

PERMEABILITY

Back 36

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

Front 37

VOID RATIO

Back 37

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

Front 38

PERVIOUS SOIL

Back 38

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

Front 39

IMPERVIOUS SOIL

Back 39

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

Front 40

COMPACTION

Back 40

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.

Front 41

OPTIMUM MOISTURE CONTENT

Back 41

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

Front 42

SHEARING STRENGTH or SHEARING RESISTANCE

Back 42

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.

Front 43

Palustrine Wetland

Back 43

All nontidal wetlands dominated by trees, shrubs, persistent emergents, emergent mosses or lichens, and all such wetlands that occur in tidal areas where salinity due to ocean-derived salts is below 0.5 ‰.

Wetlands within this category include inland marshes and swamps as well as bogs, fens, tundra and floodplains.

Front 44

Lacustrine Wetland

Back 44

includes permanently flooded lakes and reservoirs (e.g., Lake Superior), intermittent lakes (e.g., playa lakes), and tidal lakes with ocean-derived salinities below 0.5 ‰

Front 45

Marine Wetland

Back 45

Coastal wetlands include sand or pebble shores, estuarine lakes and lagoons, coastal floodplainforest, dune swamps, mudflats, coastal lakes, coastal floodplains, mangrove and saltmarsh swamps.• Marine wetlands are saltwater wetlands exposed to waves, currents and tides in an oceanic setting.

Front 46

Riverine Wetland

Back 46

includes all wetlands and deepwater habitats contained within a channel, with two exceptions: (1) wetlands dominated by trees, shrubs, persistent emergents, emergent mosses, or lichens, and (2) habitats with water containing ocean-derived salts in excess of 0.5 ‰.

Front 47

Estaurine Wetlands

Back 47

tidal wetlands that are usually semi-enclosed by land but have open, partly obstructed or sporadic access to the open ocean, and in which ocean water is at least occasionally diluted by freshwater runoff from the land

Front 48

Marsh

Back 48

Marshes are defined as wetlands frequently or continually inundated with water, characterized by emergent soft-stemmed vegetation adapted to saturated soil condition. All types receive most of their water from surface water, and many marshes are also fed by groundwater.

Front 49

Swamp

Back 49

Swamps are characterized by saturated soils during the growing season and standing water during certain times of the year. The highly organic soils of swamps form a thick, black, nutrient-rich environment for the growth of water-tolerant trees

Front 50

Bog

Back 50

characterized by spongy peat deposits, acidic waters and a floor covered by a thick carpet of sphagnum moss. Bogs receive all or most of their water from precipitation rather than from runoff, groundwater or streams. Alkaline

Front 51

Fen

Back 51

peat-forming wetlands that receive nutrients from sources other than precipitation: usually from upslope sources through drainage from surrounding mineral soils and from groundwater movement. Acidic