Stress–dilatancy relationship for railway ballast

A New Technique for Quality Assessment of Railway Ballast Materials

The influence of main quality tests on the overall quality of railway ballast materials is assessed in this study. The need to integrate all acceptance tests in a unified manner for precise evaluation of ballast quality is identified, and a technique of performing this is proposed. Using this approach, a new ballast quality index (BQI) is defined in which, the main acceptance tests including ab...

Calibration Of Railway Ballast DEM Model

The ballast of the railway track is constantly changing due to dynamic forces of train traffic that results in the crushing of the rocks. The feasibility to simulate each particle makes the discrete element method (DEM) suitable for the task. Different DEM particle models are introduced in our paper and the adequate one was chosen. This new method is based on crushable convex polyhedral element...

Statistical monitoring for continual quality control of railway ballast

Existing quality controlmethods for railway ballast are arduous and expensive since they are based onmanual material inspections. Thus, test intervals are typically fairly wide. As a consequence, short-term andmid-term fluctuations of ballast quality may not be detected. This results in increased costs for maintenance work such as tamping. To make test intervals shorter and even allow for conti...

Herbicide partitioning to concrete, asphalt and railway ballast

Parametrisation of a DEM model for railway ballast under different load cases

The prediction quality of discrete element method (DEM) models for railway ballast can be expected to depend on three points: the geometry representation of the single particles, the used contact models and the parametrisation using principal experiments. This works aims at a balanced approach, where none of the points is addressed with excessive depth. In a first step, a simple geometry repres...