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Aggregate Abrasion Value - the standard measure of an aggregate’s resistance to abrasion.


The authority as defined in the Act.

Bond coat

Proprietary materials certified by a Product Acceptance Scheme, generally formulated to provide cohesion between bituminous layers.

CBGM base Cement bound granular mixture – a mixture of controlled graded aggregate using cement that sets and hardens by hydraulic reaction. This is a specific type of relatively strong hydraulically bound material (HBM) typically used for base layers in composite roads.
CBR California bearing ratio - a penetration test for the mechanical strength of soils and granular materials.
Composite footway, footpath or cycle track construction A pavement comprising lean mix concrete or other hydraulically bound material (including cement bound granular mixtures) overlaid with a bituminous surface course or a bituminous surface and binder course.
Composite road construction A pavement comprising concrete, lean mix concrete, CBGM base or some other hydraulically bound granular material with a bituminous overlay of 100 mm or more. Where the bituminous overlay is less than 100 mm or there is no bituminous overlay, the pavement is considered rigid.
Cut-back See ‘stepped joint’.
Cycle track A way constituting or comprised in a highway, being a way over which the public have a right of way on pedal cycles only, with or without a right of way on foot.
Deep opening Any opening, excavation, core or trench where the depth of cover over the apparatus is greater than 1.5 m but not including openings with a depth of cover intermittently greater than 1.5 m over lengths of less than 5 m.
DMRB Design Manual for Roads and Bridges.
Emergency works Works required to prevent the occurrence of circumstances likely to cause danger to persons or property. See S52 of the Act for the formal definition.
FCR Foamed Concrete for Reinstatements.
Flexible construction A structure where the base comprises a bituminous or granular material, or a combination thereof.
Footpath A way over which the public has a right of way on foot only, not being a footway.
Footway A way comprised in a highway, which also comprises a carriageway, being a way over which the public has a right of way on foot only.
Geosynthetic materials A generic term describing a product at least one of whose materials components is made from a synthetic or natural polymer in the form of a sheet or a 3D structure and used in contact with soil or other materials in geotechnical and civil engineering applications.
HBM Hydraulically bound material – material comprising a mixture of soil and/or graded granular material with hydraulic binder and water that sets and hardens by hydraulic reaction.
Immediate reinstatement Works comprising the orderly replacement of excavated material, reasonably compacted to finished surface level, usually with a cold-lay surfacing. This technique is used when it becomes necessary to temporarily reinstate an excavation to permit immediate trafficking.
Interim reinstatement The orderly placement and proper compaction of reinstatement layers to finished surface level, including any temporary materials.
Intervention Repair to a compliant condition of a reinstatement that does not comply with the performance requirements of this Code.
LA Los Angeles abrasion value – a measure of an aggregate’s resistance to abrasion.
Large diameter core A core over 150 mm in diameter.
Major works Standard works that have been identified specifically in the undertaker’s annual operating programme or which, if not specifically identified in that programme, are normally planned at least 6 months in advance of works commencing.
MCHW Manual of Contract Documents for Highway Works.
Micro trench An opening up to 60 mm wide and over 1 m long.
Modular construction A structure where the surface comprises setts, concrete blocks, brick pavers or paving slabs etc. laid on an appropriate sub-construction.
msa Million standard axles – based on the expected traffic to be carried over 20 years. See S1.3.
Narrow trench An opening over 60 mm and up to 300 mm wide and over 1 m long.
NRSWA See "The Act".
Other openings Any opening, excavation or core that is not a micro trench, a narrow trench, a large diameter core, a small opening or a deep opening.
Pen The penetration grade of a bituminous binder.
Permanent reinstatement The orderly placement and proper compaction of reinstatement layers up to and including the finished surface.
PMMA Polymer modified mastic asphalt to BS EN 13108-6.
Preferred The favoured choice between permitted options.
Product Acceptance Scheme Product Acceptance Scheme in accordance with 100 Series of the MCHW, Clauses 104.15 and 104.16 (such as British Board of Agrément certificates).
PSV Polished Stone Value.
Restricted area Small openings, openings less than 200 mm wide or other areas where conventional compaction equipment cannot be used effectively.
Rigid construction A pavement quality concrete surface slab (that may be reinforced) which also performs as the base or a concrete base with less than 100 mm bituminous overlay. Where the bituminous overlay is 100 mm or more the pavement is considered to be composite.
Road & footway structure The surface course, binder course, base and sub-base.
Small features Frames and surface boxes smaller than 600 mm x 600 mm.
Small openings

An excavation with a reinstatement surface area, excluding the apparatus surface area, up to 2 m2 in road types 0, 1 and 2 and up to 4 m2 in road types 3 and 4 and in footways, footpaths and cycle tracks, that is not a large diameter core, a micro trench or a narrow trench.

SRV Skid Resistance Value – a measure of the frictional properties of a surface using a pendulum test device.
Stepped joint A step where the reinstated binder and/or surface courses are made wider than the reinstatement below to provide higher resistance to water ingress.

The whole or any part of the following, irrespective of whether it is a thoroughfare:

  1. any highway, road, lane, footway, alley or passage,
  2. any square or court, and
  3. any land laid out as a way whether it is for the time being formed as a way or not; and for the avoidance of doubt includes land on the verge of a street or between two carriageways. Where a street passes over a bridge or through a tunnel, references to the street include that bridge or tunnel (NRSWA Section 48 etc.).
Street manager As referred to in the Act, Section 49(4).
Surface treatment A thin protective layer (e.g. surface dressing) applied to the surface to restore skid resistance and/or to seal it. This does not include high amenity or high duty surfaces, or surfaces with an aesthetic requirement.
The Act The New Roads and Street Works Act 1991 (NRSWA).
Trim-line The cut face that defines the outer edge of an excavation at the surface.
Trimback The area between the trim-line and a fixed feature and the edge of an excavation.
UKAS United Kingdom Accreditation Service.
Undertaker A person with a statutory right to execute street works or the holder of a street works licence.
Verge The area of the highway outside the carriageway (and footway if present). A verge may be slightly raised but is exclusive of embankment or cutting slopes and is generally grassed.
Wheel tracking A test to determine the resistance to deformation (rutting) of, primarily, surface courses.