Los Angeles trial
The Los Angeles test is a test method and is used to determine the resistance of the aggregate of a concrete surface (e.g. concrete roadways) or asphalt to fragmentation (so-called impact stress). This test method is used to determine the Los Angeles coefficient.
Test procedure
At the beginning of the test, a 5 kg (± 5 g) rock sample with a grain size of 10 mm to 14 mm together with eleven steel balls (4775 ± 85 g) is placed in a steel drum. The diameter of the steel drum is standardized and should be 710 ± 3 mm. The rock sample is crushed or rubbed off by the subsequent rotation (32 ± 1 min −1 ) of the drum. After 500 revolutions, the rock sample is separated from the drum over a 1.6 mm sieve and the residue (symbol m ) is determined.
evaluation
The percentage of crushed rock is calculated from the residue determined. This is also known as the Los Angeles coefficient (symbol LA ). For an initial weight m 0 = 5 kg and the determined residue m in kg, LA is calculated as:
Individual evidence
literature
- DIN EN 1097-2: 2010-07 "Test methods for mechanical and physical properties of aggregates - Part 2: Method for determining the resistance to fragmentation" , p. 7 f.
- Günter Neroth: Wendehorst building materials science: Basics - building materials - surface protection . Springer Verlag, 2010, ISBN 3-8351-0225-7 , pp. 150 .