GLOSSARIES - Geotechnical Earthquake Engineering - page 512

occurs in areas where a cohesive soil is being deposited very rapidly and not enough time has elapsed
for the soil to consolidate under its own weight.
Void Ratio The volume of voids divided by the volume of soil solids.

GLOSSARY 4 COMPACTION, GRADING, AND
CONSTRUCTION TERMINOLOGY

Aggregate A granular material used for a pavement base, wall backfill, etc.

Coarse Aggregate Gravel or crushed rock that is retained on the No. 4 sieve (4.75 mm).

Fine Aggregate Often sand (passes the No. 4 sieve and is retained on the No. 200 U.S. standard

sieve).

Open-Graded Aggregate Generally a gravel that does not contain any soil particles finer than

the No. 4 sieve.
Apparent Opening Size For a geotextile, a property which indicates the approximate largest par-
ticle that would effectively pass through the geotextile.
Approval A written engineering or geologic opinion by the responsible engineer, geologist of
record, or responsible principal of the engineering company concerning the process and completion of
the work unless it specifically refers to the building official.
Approved Plans The current grading plans which bear the stamp of approval of the building offi-

cial.
Approved Testing Agency A facility whose testing operations are controlled and monitored by
a registered civil engineer and which is equipped to perform and certify the tests as required by the
local building code or building official.
As-Graded (or As-Built) The surface conditions at the completion of grading.
Asphalt A dark brown to black cementitious material whose main ingredient is bitumen (high mol-
ecular hydrocarbons) that occurs in nature or is obtained from petroleum processing.
Asphalt Concrete (AC) A mixture of asphalt and aggregate that is compacted into a dense pave-
ment surface. Asphalt concrete is often prepared in a batch plant.
Backdrain Generally a pipe and gravel or similar drainage system placed behind earth retaining
structures such as buttresses, stabilization fills, and retaining walls.
Backfill Soil material placed behind or on top of an area that has been excavated. For example, back-
fill is placed behind retaining walls and in utility trench excavations.
Base Course or Base A layer of specified or selected material of planned thickness constructed
on the subgrade or subbase for the purpose of providing support to the overlying concrete or asphalt
concrete surface of roads and airfields.
Bench A relatively level step excavated into earth material on which fill is to be placed.
Berm A raised bank or path of soil. For example, a berm is often constructed at the top of slopes to
prevent water from flowing over the top of the slope.
Borrow Earth material acquired from an off-site location for use in grading on a site.
Brooming The crushing or separation of wood fibers at the butt (top of the pile) of a timber pile
while it is being driven.
Building Official

The city engineer, director of the local building department or a duly delegated

representative.
Bulking The increase in volume of soil or rock caused by its excavation. For example, rock or dense
soil will increase in volume upon excavation or by being dumped into a truck for transportation.