Road and Transport Works Terms & Definitions

Below are terms, words or expressions used in road works specifications tenders, communications and other project documents. These shall have the meanings hereby assigned to them.

Aggregate: Hard mineral elements of construction material mixtures, for example: sand, gravel (crushed or uncrushed) or crushed rock.

Anchorage: Anchorage is the device comprising all the components and materials required for retaining the force in a tensioned tendon and to transmit this force to the concrete of the structure.

Anchorage reinforcement: Anchorage reinforcement is the spiral and other reinforcement which forms part of the anchorage and is required for strengthening the anchorage and/or assisting in transmitting the tendon force to the concrete.

Angle of Slope: Unless otherwise stated, is given in terms of the ratio of the vertical difference in elevation between any two points and the horizontal distance between them. This ratio may also be expressed as a percentage.

Arising Tool: A tool used to round off the edge of a concrete slab.

Asphalt: A mixture to predetermined proportions of aggregate, filler and bituminous binder material prepared off the road and usually placed by means of a paving machine.

Asphalt Concrete: A mixture to predetermined proportions of aggregate, filler and bituminous binder material plant mix and usually placed by means of a paving machine.

Asphalt Surfacing: The layer or layers of asphalt concrete constructed on top of the road base.

Back Fill: Excavated material, which is placed and compacted in trenches and around foundations.

Base: A layer of material constructed on top of the sub base, or in the absence thereof, the selected layer. A base may extend to outside the travelled way.

Batter Board: A board of wood fixed to posts at the top of cuttings or the bottom of embankments which indicates the slope at which the cutting or embankment is to be constructed.

Binder: A material such as bitumen, cement or lime, which is added to and mixed into aggregate, granular materials or soils to bind the mixture together.

Bitumen: A class of black or dark-colored (solid, semisolid, or viscous) cementitious substances, natural or manufactured, composed principally of high molecular weight hydrocarbons, of which asphalts, tars, pitches, and asphaltites are typical.

Bond breaker: Bond breaker is the coating or sheath placed on a tendon to prevent it from bonding to the surrounding concrete.

Bond Stone: A bond stone is an elongated prismoidal stone incorporated with the longest dimension at right angles to the face of a masonry structure to provide structural integrity.

Borrow Area/Borrow Pit: An area, within designated boundaries, outside the Permanent Works, approved for the purpose of obtaining fill or pavement materials. A borrow pit is the excavated pit in a borrow area.

Borrow Material:

Borrow material is a general term used to describe material obtained from a borrow pit.

Boulder: A fragment of rock, usually rounded by weathering or abrasion, with a minimum dimension of 200mm or more.

Bridge: A structure erected over a depression, river, watercourse, railway line, road or other obstacle for carrying motor, railway, pedestrian or other traffic or services and having a length, measured between abutment faces along the centerline of the superstructure, of 6 meter or more.

Bursting reinforcement: Bursting reinforcement is the reinforcing steel required in and adjacent to the anchorage zones to resist the tensile stresses induced in the concrete by the anchorage(s).

Cable: Cable is the tendon. together with the anchorage, sheathing and all fittings.

California Bearing Ratio (CBR): The California Bearing Ratio (CBR) of an untreated soil or gravel as determined by means of Method A8 of TMH1 is the load in Newtons, expressed as a percentage of California standard values, required to allow a circular piston of 1,935 mm2 to penetrate the surface of a compacted material at a rate of 1.27 mm per minute to depths of 2.54 , 5.08 and 7.62 mm. The California standard values for these depths are 13.344, 20.016 and 25.354 kN respectively.

Capping Layer: A layer of selected fill material placed on the top of the topmost embankment layer or the bottom of excavation.

Carriageway: That portion of the roadway including the various traffic lanes and auxiliary lanes but excluding shoulders.

Catchwater Drain or Bank: A longitudinal drain or bank outside the road prism for diverting water that would otherwise flow into the road prism.

Cemented Material: Material in an existing pavement which cannot be broken up with the tines of a type 1400 caterpillar or similar road grader. Cemented crushed stone is cemented material constructed with crushed stone. An existing stabilized pavement layer will not necessarily be classified as cemented material.

Channel: A natural or artificial water course.

Characteristic strength: Characteristic strength of prestressing steel is the manufacturer’s guaranteed tensile strength below which no more than 5 per cent of the test results in a statistical population shall fall.

Characteristic Strength of Concrete: The characteristic strength of concrete is that strength below which only a pre-selected proportion of test results (i.e 1%, 2% or 5%) are expected to fall.

Chippings: Chippings are single sized particles of crushed rock, crushed boulders, crushed cobbles or crushed gravel used for surface dressing.

Coarse Aggregate: Coarse aggregate is material retained on the 4.75mm sieve.

Cobble: A fragment of rock, usually rounded by weathering or abrasion, with a minimum dimension of 60mm and a maximum dimension of 200mm.

Coefficient of Uniformity: The coefficient of uniformity is the ratio of the sieve size through which 60% by mass of the material passes to the sieve size through which 10% by mass passes.

Compliance Testing: Testing of the completed works to ascertain compliance of the requirements of the Specification.

Coupler: Coupler is the device comprising all components required to join up two tendons.

Crushed Particle: A crushed particle is a particle of coarse aggregate, which has at least three fractured faces when obtained by crushing rock and boulders, and at least two fractured faces when obtained by crushing gravel.

Crushed Ratio: The crushed ratio is the percentage of crushed particles of coarse aggregate in the total number of particles of coarse aggregate.

Culvert: A drainage structure which provides an opening under the carriageway or median for the passage of water.

Curing Compound: A liquid which is applied as a surface coating to (newly placed) concrete and hardens to form a membrane that inhibits the evaporation of moisture from the concrete.

Cut: Cut shall mean all excavated material from the road prism including side drains.Terms and Definitions for Road Cross Section Elements

Cutting: That portion of the road prism from where material is excavated to sub-grade or road bed level.

Deflector: Deflector is the device used to deflect a tendon alignment within a structural element.

Duct: Duct is the void formed to house the tendon (s) and may be formed by coring, or by using sheaths or by way of extractable cores.

Earthworks: The excavation of material from cuttings and/or the construction of embankments.

Embankment: That portion of the road prism composed of approved fill material, which lies above the original ground and is bounded by the side slopes, described in the Contract, extending downwards and outwards from the outer shoulder breakpoints and on which the pavement is constructed.

Equipment: All machinery, together with the necessary supplies for upkeep and maintenance, and also all tools and apparatus necessary for the proper construction and acceptable completion of the work.

Excess Overburden: Overburden within a borrow area which is not required or is unsuitable for use in construction.

False work: Support for concrete formwork.

Fill: Material which is used for the construction of embankments.

Filler: Processed or naturally occurring material passing the 75 micron sieve which is principally used to improve the combined aggregate grading and thus reduce the air voids content of bituminous mixtures.

Fine Aggregate: Fine aggregate is crushed or naturally occurring material passing the 4.75mm sieve.

Footway: An area normally adjacent to the carriageway provided for the use by pedestrians.

Formwork: Temporary boarding or sheeting erected to contain concrete during placing, compacting and initial hardening.

Furrow Ditch: A longitudinal drain or bank outside the road prism for diverting water that would otherwise flow onto the road prism.

Gabions: Gabions consist of woven steel mesh boxes or mattresses filled with stone.

Grade line: The grade line is a reference line in the drawings of the longitudinal sections of the road indicating at regular intervals the elevations according to which the road is to be constructed. The grade line may refer to the level of the completed road, base or any other layer and may indicate the elevations either along the carriageway center line or along any designated position on the road cross-section.

Grading Modulus(GM): The cumulative percentages by mass of material in a representative sample of aggregate, gravel or soil retained on the 2.00mm, 0.425mm and 0.075mm sieves, divided by 100.

Gravel: Gravel is naturally occurring, rounded, granular material with a particle size of from 2mm to 60mm. (It does not apply to Gravel Wearing Courses).

Grout Check: A recess formed at concrete construction joints, which may be filled with grout; to mask, and ensure a straight line to, the joint.

Highway: A general term denoting a public way for purposes of vehicular travel, including the entire area within the right -of – way.

Inlet and Outlet Drainage Channels: Channels leading into or discharging from culverts, storm-water drains and minor bridges.

Inspector: The authorized representative of the Engineer assigned to make detailed inspections of materials or contract performance.

Kicker: A concrete plinth at least 70mm high above the concrete floor, forming the start of a concrete wall or column.

Lane: Part of a travelled way intended for a single stream of traffic in one direction, which has normally been demarcated as such by road markings.

Leveling Course(s): One or more layers of asphalt or granular material, of varying thickness, which are applied to improve the regularity of an existing road surface.

Lot: A sizable portion of work or quantity of material which is assessed as a unit for the purpose of quality control and selected to represent material or work produced by essentially the same process and materials.

Masonry: Stonework constructed with interlocking stones more than one stone thick.

Median: The area between the two carriageways of a dual carriageway road.

Median Drain: A longitudinal drain situated in the median of a dual carriageway road.

Milling: Excavating and removing a layer of material exceeding 10 mm in thickness from an existing pavement by means of an approved milling machine. Milling is normally used only in asphalt and cemented layers.

Mitre Drain/Mitre Bank: A Mitre Drain is a drain constructed at an angle to the centerline of the road to divert water from the side drains. Mitre drains will include mitre banks placed across side drains.

Mortar: A mixture of fine aggregate, cement and/or hydrated lime usually in predetermined proportions, with water, to create a fine grained cementitious material suitable for the bedding of bricks and masonry etc.

Optimum Moisture Content for Compaction: The moisture content of a soil calculated on the basis of dry weight of soil at which the soil can be compacted to the approximate maximum density under a specified standard method of compaction.

Overburden: Overburden is unsuitable material which overlies suitable material within a borrow pit or quarry.

Overlay: An additional pavement layer applied on top of an existing road for strengthening the pavement and/or for improving the riding quality.

Parking Lane: An auxiliary lane adjoining the travelled way for the purpose of vehicular parking.

Pavement: A multi-layered horizontal structure which is constructed for the purpose of carrying traffic.

Pavement Layers: The layers of different materials, which comprise the pavement structure.

Pavement Planning: Planning of an existing road surface by the removal of a layer of material by means of a milling machine or other equipment.

Pioneer Layer: An initial layer constructed over a weak roadbed where selected material is used to provide a stable platform for the construction of subsequent layers.

Prestress: Prestress is the stress induced in concrete by tensioned tendons.

Prestressed concrete: Prestressed concrete is structural concrete in which effective internal stresses are induced by means of tensioned tendons.

Pre-stressing: Pre-stressing is the inducement of compressive stress into a structural concrete element either by pre-tensioning or post-tensioning tendons comprising of cables, wires or bars incorporated into the element.

Pre-tensioned concrete: Pre-tensioned concrete is prestressed concrete where the tendon is tensioned before the concrete has been cast.

Post-tensioned concrete: Post-tensioned concrete is prestressed concrete where the tendon is tensioned after the concrete has hardened.

Prime Coat: A bituminous treatment applied to the surface of a newly constructed unbound road base prior to the construction of a bituminous layer or surface treatment.

Project Specifications: The specifications relating to a specific project, which form part of the contract documents for such project, and which contain supplementary and/or amending specifications to the standard specifications.

Pull-in: Pull-in is the elastic shortening of the tendon caused by relative movement between the anchorage or coupler components on account of seating and gripping action during or immediately after transfer.

Quality Control: Procedures, and/or testing, carried out prior to, or during, the construction of the Works for the purpose of ensuring compliance with the requirements of the Specification.

Quarry: An area within designated boundaries, approved for the purpose of obtaining rock.

Recycling: The processing of salvaged material in a plant for re-use.

Rehabilitation: Work undertaken to significantly extend service life and improve the condition or riding comfort of an existing road.

Reinforcement for Asphalt: A cloth or grid of synthetic material placed underneath or between asphalt layers for strengthening the asphalt.

Release: Release is the specified elastic shortening of the tendon at the anchorage achieved before or during transfer.

Retexturing: Treatment of an existing road surface to restore the texture to a specified depth of texture or skid resistance.

Right-of – Way: The land secured and reserved by the Department for the construction and maintenance of highway.

Rip-rap: Unbonded stone provided to protect the surfaces of slopes and the beds of watercourses from erosion and scour.

Road Base: A layer of material of defined thickness and width constructed on top of the sub-base, or in the absence thereof, the sub-grade. A road base may extend beyond the carriageway.

Road Bed: The natural in-situ material on which the embankment or capping layers are to be constructed.

Road Bed Material: The material below the road bed extending to such depth as affects the support of the embankment structure or capping layer.

Road Prism: The cross sectional area bounded by the original ground level and the sides of slopes in cuttings and embankments excluding the pavement.

Roadside: The portion of the highway outside the roadway.

Road Reserve: The entire area (Carriageways, median, side drains and catch water drains) included by the boundaries of a road as proclaimed.

Roadway: The roadway comprises the carriageway, shoulders and median.

Rock: A mass of hard mineral material which, when excavated, requires the use of explosives, sawing or splitting by mechanical means.

Roller Passes: Unless otherwise specified in the specifications or the project specifications, an area will be taken to have received one roller pass when a roller has passed over such area once. Additional passes made only as a result of nominal overlapping so as to ensure full coverage shall not be taken into account.

Scabbing: The use of a hand-held or self supporting percussion machine to remove the surface of hardened concrete without damaging the structure.

Scarify: Loosen and break-up soil or existing pavement layers by means of a machine fitted with tines.

Screed: A layer of fine-graded asphalt or slurry placed to fill in slacks in existing seals and to improve the riding quality of the road.

Seal: The application of one or more layers of bituminous binder with or without layers of crushed stone, sand or slurry in successive layers on the carriageway, shoulders or on any other compacted layer on which movement of traffic takes place.

Selected Layer: The lower layer or layers of the pavement, which is constructed, direct onto the fill, or in some cases the roadbed. It may include roadbed material compacted in- situ.

Services: Cables, pipes or other structures to provide, inter alia, conduits for electricity, telephone and telegraph connections, water, sewage, etc.

Sheath: Sheath is the tube or casing enclosing the tendon and which temporarily or permanently allows a relative movement between the tendon and the surrounding concrete.


(a) When referring to this as a surface: The area between the outside edge of the travelled way and the shoulder breakpoint.

(b) When referring to this as a pavement layer: The upper pavement layer lying between the outside edge of the base and the shoulder breakpoint.

Shoulder Breakpoint: The point on a cross section at which the extended flat planes of the surface of the shoulder and the outside slope of the fill and pavement intersect.

Side Drain: A longitudinal drain offset from, and parallel to, the carriageway.

Side Fill: Side fill is either surplus or additional fill which is used to extend and flatten the slope of an embankment and which is often compacted to a lower standard than the former.

Sidewalk: The portion of the roadway primarily constructed for the use of pedestrians.

Skew or Skew Angle: The acute angle formed by the intersection of a line normal to the centerline of the roadway with a line parallel to the centerline of bents, piers or abutments of a bridge, or in the case of a culvert, with the centerline of the culvert barrels.

Slope: Unless otherwise stated, slope is given in terms of the ratio of the vertical difference in elevation between any two points and the horizontal distance between them. The ratio may also be expressed as a percentage.

Spalls: Chipped or splintered fragments of stone.

Specifications: The general term comprising all the direction, provisions and requirements contained herein, entitled “ERA Standard Technical Specification for Road Works -2001”, together with such as may be added or adopted as supplemental specifications or as special provisions, and all documents of any description, including notes on plans, pertaining to the method and manner of performing the work or to the quantities and qualities of materials to be furnished under the contract.

Spoil ( Material): Surplus material originating from construction operations.

Stabilization: The treatment of pavement materials by the addition of lime or Portland cement.

Stone Pitching: A single course of stones placed on edge with spalls rammed into the spaces between the stones.

Structures: Bridges, culverts, catch basins, drop inlets, manholes, retaining walls, cribbing, end walls, buildings, sewers, service pipes, underdrains, foundation drains, and other miscellaneous items, which may be encountered in the work, and which are not classified herein.

Sub-base: The pavement layer of material of specified dimensions on top of the sub-grade and below the road base.

Subcontractor: Any individual, firm or corporation to whom the Contractor sublets any part of the contract.

Sub-grade: The surface upon which the pavement structure and shoulders are constructed.Road Construction Terminology Glossary

Substructure: All of that part of the structure below the bridge seats or bellow the spring lines of concrete arches. Back walls and wing walls of abutments shall be considered as parts of the substructure.

Sub-surface Drain (Sub-soil Drains): A covered drain constructed to intercept and remove sub-soil water. It includes all pipes and filter material in the drain.

Surface Dressing: The sealing or resealing of the surface of the carriageway or shoulders by means of one or more successive applications of bituminous binder and chippings.

Tack Coat: A bituminous treatment applied to the surface of an existing bituminous layer prior to the construction of a new bituminous layer.

Tendon: Tendon is the prestressing steel consisting of the bar, wire or strand individually placed, or of bars, wires or strands placed in a duct, all of which are tensioned to impart prestress to a concrete member.

Tensioning: Tensioning is the action of inducing and regulating the force in a tendon by means of tensioning and measuring equipment.

Texture Treatment: Treatment of an existing road surface to obtain a uniform texture.

Topsoil: A surface layer of soil, which contains organic matter and is capable of supporting the growth of vegetation.

Traffic: Vehicles, pedestrians and animals travelling along a route.

Traffic Lane: Part of a carriageway intended for a single stream of traffic in one direction, which has normally been demarcated as such by road markings.

Transfer: Transfer in the case of post-tensioned concrete is the action of transferring the tensioning force from the tensioning equipment (jack) to the anchorage. Transfer in the case of pre-tensioned concrete is the action of transferring the force in the tensioned tendon(s) to the concrete.

Transmission length: Transmission length is the tendon length required to transmit via bond stresses the full force in the tendon to the concrete.

Travelled Way: That portion of the carriageway, which includes the various, traffic lanes and auxiliary lanes but exclude the shoulders.

Unbound Material: Naturally occurring or processed material, which is not bound together by the addition of a binder such as cement, lime or bitumen.

Verge: The area between the outer edge of the road prism and the boundary of the road reserve.

Wheel Track: The path followed by the wheel of a vehicle during normal riding movements. The wheel tracks cover approximately the outer meter width on both sides of a traffic lane.

Working Drawings: Stress sheets, shop drawings, erection plans, false work plans, cofferdam plans, bending diagrams for reinforcing steel, or any other supplementary plans or similar data which the contractor is required to submit to the Engineer for approval.

Work in restricted areas: No additional or extra over payment will be made for work in restricted areas, unless the items of work to which it will apply and the pay items under which payment will be effected, are explicitly specified in these standard specifications or in the project specifications and listed in the schedule of quantities.

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