PMC

Position diagram for measurements of pressure between the rail and sleeper and accelerations of the ballast particle and sleeper. Accelerometers for the ballast particle were installed in the ballast layer below 10 cm from the bottom of sleeper. Accelerometers for the sleeper were installed on top of the sleeper.

Number of contacts versus number of load cycles: ballast contacts with a sleeper, b next layer (defined as ballast–ballast contacts, where one contact partner is also in contact with the sleeper) and c in the full assembly, for Kieselkalk in steel box. Red and green data sets represent results for the concrete sleeper and concrete sleeper with respectively (color figure online)

Finite element (FE) model of the ballasted track structure: (a) Geometry, boundary conditions, loads, concentrated masses and spring-dashpot systems (layers: grey—rails, green—sleeper, yellow—ballast, orange—protection layer, brown—soil subgrade); (b) FE mesh.

Rheological model of the ballasted track structure: (a) Reference model; (b) Model with USP; (c) Rheological model of USP. Symbols: A-B—subgrade surface layer; I—rolling stock, II—railway track structure, III—subgrade; 1—non-spring part of the rolling stock, 2—rail, 3—rail pad, 4—sleeper, 5—ballast, 6—subgrade, 7—USP.