DIV 2

American Association of State Highway and Transportation Officials

AASHTO

American National Standards Institute

ANSI

American Society for Testing Materials

ASTM

Department of Public Works and Highways

DPWH

Unified Soil Classification System

USCS

AASHTO Soil Classification System

Classifies inorganic soils for suitability as subgrade materials in terms of good drainage and bearing capacity.

Boulders

Soil classification pertaining particle sizes above 75mm.

Gravel

Soil classification pertaining to particle sizes 75mm to no.10 sieve.

Coarse Sand

No.10 to No.40 sieve soil classification.

Fine Sand

No.40 to No.200 sieve soil classification

Silt-Clay Particles

Soil classification passing no.200 sieve

Atterberg Limits

Tests performed on soils passing the No.40 sieve.

Liquid Limit (LL)

Moisture content at which a soil changes from the liquid state to the plastic state, measured when soil in a shallow dish flows to close a 12.5 mm groove after 25 drops from 1 cm.

Plastic Limit (PL)

The water content at which a silt or clay material will just begin to crumble when rolled into a thread approx 3.2mm (1/8inch) in diameter.

Plasticity Index (PI)

Defined as the Liquid Limit minus the Plastic Limit : LL - PL = PI , that is the range of water content over which sediment behaves.

Fill materials

Soil, crushed stone, and sand used to raise an existing grade, or as a man-made-deposit; generally used under footings, pavers, or concrete slabs on grade.

Granular Fill or Filters

Soil materials with sand equivalent of not less than 50%; used to prevent the movement of fine particles out of soils and other natural materials through which seepage occurs; conforming to ASTM C 33, size 67.

Borrow Fill

Selected laboratory-approved pit-run gravel, disintegrated granite, sand, shale, cinders or other similar materials with not more than 35% fraction passing the No.200 sieve.

Base Course Materials

Hard durable fragments of stone and a filler of sand or other finely divided mineral matter, free from vegetable matter and lumps of clay.

Riprap (Rock Lining)

A constructed layer or facing of stone, placed to prevent erosion, scour or sloughing of a structure or embankment.

Gabion System

Wire-enclosed riprap, consists of mats or baskets fabricated from wire mesh, filled with small riprap, and anchored to a slope.

Geosynthetics

Construction materials consisting of synthetic components made for use with or within earth materials.

Geotextiles

Most common geosynthetics, and consist of woven or nonwoven fabric made from polymeric materials such as polyester or polypropylene generally used for reinforcement, separation, filtration, and in-plane drainage.

Geotextile Reinforcement

When the geotextile fabric lends its strength to low loadbearing soil to increase the overall design strength and decrease the amount of sub-base and base course material.

Geotextile Separation

When the geotextile is placed between dissimilar materials to prevent migration of one of the materials into the other.

Geotextile Filtration

When the geotextile is used to prevent the movement of fine particles from soil through which seepage occurs.

Subsurface Filtration

Category of geotextile filtration employed in sub-surface drainage applications, such as filters around under-drains or edge drains, or under paving.

Erosion Control

Category of geotextile filtration employed to protect cut slopes or drainage features. When used in conjunction with a stone lining or riprap, they would serve a secondary function of separation.

Sediment Control

Category of geotextile filtration are exclusively those used for silt fence applications. While they serve the purpose of "filtering" runoff, the mechanism by which they function is different than subsurface drainage or erosion control applications.

In-Plane Drainage

Particular thick-needled nonwoven geotextiles having sufficient in-plane flow capacity for use as flow conduits in drainage applications.

Geomembranes

Continuous polymeric sheets that are impermeable.

Geocomposites

Consist of a combination of geosynthetic components; are usually sheet or edge drains consisting of a prefabricated core to which a geotextile filter is bonded.

Geonet

A type of geosynthetic that consists of a continuous extrusion of polymeric ribs that form void space through which provide in-plane flow capacity.

Geocell

Three-dimensional prefabricated polymeric systems ranging from 100 to 200 mm (4 to 8 inches) high. Originally developed to rapidly stabilize soft subgrades for mobilization of large equipment, they are now frequently used for protection and stabilization of steep slope surfaces and protective linings for channels.

Termite Proofing

Three types include physical barriers, chemical barriers, and colony elimination (bait) system.

Termite Resistant Sand

A layer of sand with uniform size particles. The sand must be large enough to prevent the termite from moving through it effectively and of a consistency that prevents its use in "tunnel" construction. Sometimes used around the foundation of a home during construction.

Termite Mesh

Steel mesh product that is fine enough to keep even tiny termites from passing through it. Termite Mesh is used in slab construction (concrete slabs are poured over or with the mesh). It is also used to wrap pipes and other access areas.

Vertical Barriers

Created by applying 4 gallons of termiticide per 3 linear meters by rodding or trenching around the base of foundations, plumbing, utility entrances, expansion joints, and where two slabs will join.

Horizontal Barriers

Made by applying 4 liters (one gallon) of termiticide per 3 square meters. The treatment is usually accomplished by applying a coarse spray at low pressure. All termite treatments to slab construction should include horizontal barriers, which are relatively easy to apply.

Colony Elimination (Bait) System

The objective of this method is to attract the termite workers to forage on a slow-acting insect growth regulator (IGR) called hexaflumuron that will work to eliminate the termite workers population and eventually result in the death of the queen and any subsequent future queens, and therefore the entire colony.

Choker Course

Filter layer of finer material that is installed over a coarse road base material. Its purpose is to provide a stable foundation of fine-grained aggregate for the construction of a pavement.

Hot Mix Asphalt

A dark brown to black cementitious material, solid or semi-solid, composed of bitumens which when mixed with graded aggregates is used as paving material by placing, shaping, and compacting while hot over a prepared base.

Cold Mix Asphalt

Asphaltic concrete prepared with a relatively light and slow-curing asphalt, placed over a prepared surface without heat. This hardens to a state that is less firm and durable than hot-mix asphaltic concrete.

Asphaltic Macadam

Paving for roads and other surfaces formed by grading and compacting layers of crushed stone or gravel, then the top layer is bound by asphalt to stabilize the stone, provide a smoother surface, and seal against water penetration.

Asphalt Overlay

An asphalt leveling course made of an asphalt and aggregate mixture of variable thickness to correct the contour of existing surface, are placed on existing pavement.