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BS812: Part 114: 1989 (Pr EN 1097-8)


The PSV test calculates a Polished Stone Value for aggregates used in road surfaces, which gives a measure of the resistance to skidding.

The test is carried out by using two machines, S882 - the Accelerated Polishing Machine, and S885 - Skid Tester, (see separate Data Sheet for this machine). The Accelerated Polishing Machine polishes samples of aggregates, simulating actual road conditions.

Test Procedure

Fourteen specimens are clamped around the ‘road wheel’ of the PSV machine, and subjected to two stages of polishing by a loaded rubber tyre. First by corn emery, and secondly by emery flour.

Relevant Standards

BS 812 Pt 114: 1989, EN 1097-8, ASTM E303 copy of these documents are necessary to understand and carry out the test.

Users of the Test

Local Authorities, Consulting Engineers, Contractors, Asphalt Producers, and Civil Engineering Departments of Universities.

Road Safety

Use of the PSV s in road construction has had a major influence in reduction of accidents.

Machine Features

  • Heavy welded steel mainframe, standing in adjustable pads
  • High alloy ground mainspindle running in sealed ball bearings additionally protected by a labyrinth seal, spindle axially loaded to eliminate end play
  • TEFC motor with adjustable timing belt drive
  • Predetermined revolution counter
  • Specimens manufactured and easily removed from accurately machined moulds
  • Specimens located on ‘Road Wheel’ by rubber rings and held by simple side fixing
  • Tyred wheel easily removed for replacing tyres
  • Water gravity fed from high level tank through calibrated flowmeter
  • Used abrasive and water collected in removable tray
  • Loaded tyre raised and lowered to the running surface by machanical lifting device
  • Electrical supply protected by ‘no volt’ release
  • Feeder and control curcuits 24 volt for safety
  • Protection by easily removed covers and guards
  • Safety switch to ensure removable saftey covers are in place
  • Supplies

    Corn Emery, Emery Flour, Control Stone and Criggion Stone can be supplied. Operating instructions and wiring diagrams are supplied with each machine.

    Physical Data

    Machine Packed: Width 73 81 cms x Depth 63 79 cms x Height (Frame) 79 123 cms
    Height (Water Tank) 155 cms
    Volume .79 cu: metres
    Weight 175 205 kg
    Electrical Supply 230V/110V. 50/60 HZSingle phase 13 amp.

    USA Specification

    Machines can be supplied with 110 V. 60
    Hz motors pneumatic tyres and ASTM weight.
    Skid Resistance Tester is also required to determine PSV.