"Ku\u010Dera, Petr" . . "978-83-926896-4-5" . . "[5B11E3857443]" . "Pozna\u0148" . "triaxial testing; railway ballast; cyclic loading; Young's modulus; aggregates"@en . "Pozna\u0148" . "Proceedings of the 5th International Interdisciplinary Technical Conference of Young Scientists" . "S" . . . "The triaxial testing units allow determination of strength parameters of granular materials such as soils and aggregates. Commonly, the triaxial cells are designed for testing specimens with diameter of up to 150 mm, and thus for testing materials with maximum grain size of approx. 30 mm. At some European universities large triaxial testing units capable of testing specimens with diameter of 200 to 625 mm were developed. Considering the minimum required diameter of the specimen, which should be 5 times the maximum grain size, triaxial cells capable of testing specimens with diameter of 300 mm might be also used for testing railway ballast. This article states the experience with laboratory testing of different types of aggregates for railway ballast in a large scale conventional triaxial cell, which were gained during a research stay at the Norwegian University of Technology and Science. The laboratory tests performed were mainly focused on determination of strength parameters of aggregates and evaluation of effects of dynamic loading on aggregates wear. Each sample, which was blended according to the exact gradation, experienced 1 000 000 loading cycles. The load applied to the specimen corresponded to a stress affecting the railway ballast under the sleeper, if considering an axle load of 25 t. The axial and the radial strain were measured and the Youngs modulus was evaluated during the loading. After finishing the cyclic loading, the specimen was dismounted, the sieve analysis was carried out and the variation of gradation was evaluated. Apart from the triaxial testing, also other physical parameters of the aggregates were determined, such as the volume density, the resistance to fragmentation (Los Angeles test) and the resistance to wear (micro-Deval). For laboratory testing, three materials with different origin and different expected parameters were selected. All materials were of the same gradation 22.4/63 mm." . "RIV/68407700:21110/12:00195598" . . . . "Uczelniany Samorzad Doktorant\u00F3w Politechniki Poznanskiej" . . "RIV/68407700:21110/12:00195598!RIV13-MSM-21110___" . "The triaxial testing units allow determination of strength parameters of granular materials such as soils and aggregates. Commonly, the triaxial cells are designed for testing specimens with diameter of up to 150 mm, and thus for testing materials with maximum grain size of approx. 30 mm. At some European universities large triaxial testing units capable of testing specimens with diameter of 200 to 625 mm were developed. Considering the minimum required diameter of the specimen, which should be 5 times the maximum grain size, triaxial cells capable of testing specimens with diameter of 300 mm might be also used for testing railway ballast. This article states the experience with laboratory testing of different types of aggregates for railway ballast in a large scale conventional triaxial cell, which were gained during a research stay at the Norwegian University of Technology and Science. The laboratory tests performed were mainly focused on determination of strength parameters of aggregates and evaluation of effects of dynamic loading on aggregates wear. Each sample, which was blended according to the exact gradation, experienced 1 000 000 loading cycles. The load applied to the specimen corresponded to a stress affecting the railway ballast under the sleeper, if considering an axle load of 25 t. The axial and the radial strain were measured and the Youngs modulus was evaluated during the loading. After finishing the cyclic loading, the specimen was dismounted, the sieve analysis was carried out and the variation of gradation was evaluated. Apart from the triaxial testing, also other physical parameters of the aggregates were determined, such as the volume density, the resistance to fragmentation (Los Angeles test) and the resistance to wear (micro-Deval). For laboratory testing, three materials with different origin and different expected parameters were selected. All materials were of the same gradation 22.4/63 mm."@en . "Triaxial Testing of Aggregates for Railway Ballast" . "175173" . . "21110" . "Triaxial Testing of Aggregates for Railway Ballast"@en . "2012-05-16+02:00"^^ . . . . . "1"^^ . . . "4"^^ . . "Triaxial Testing of Aggregates for Railway Ballast" . "Triaxial Testing of Aggregates for Railway Ballast"@en . . . "1"^^ .