HomeAbout UsContact UsNews/EventsCareersResourcesMedia linkedintwitter facebook youtube

Lab Services: Rock testing

Back to Results

Test Method Title

Cerchar Abrasivity Index (CAI)

Reference Number

ASTM D7625

Material

Rock

Test Property

Abrasivity

Description of Test

This test method determines the abrasiveness of rock by of measuring the wear on the tip of a steel stylus caused by scratching against a freshly broken or saw cut rock surface for a prescribed 10 mm distance. Basically, the CERCHAR test is a measurement of the relative different hardness of stylus tip and rock specimen surface. Five individual CAI tests shall be conducted for each rock specimen to achieve an average value. CAI is used to assess the abrasiveness of rock for mechanical excavation. Rock abrasiveness governs the performance of disc cutters, the rate of its replacement and therefore subsequent tunnel costs.

Preferred Test Sample Size

Rock core specimens

Number of Test Specimens

1

Test Specimen Size

3 in of core minimum

Keywords

Cerchar, abrasivity, index, CAI, rock

For more information, contact GeoTesting Express:



Atlanta

770.645.6575


Boston

978.635.0424


Chicago

224.676.1371


New York

212.566.6630



info@geotesting.com

Related Information

Request Quote