Effect of confining pressure on the degradation of ballast under cyclic loading Available to Purchase

The confining pressure acting on the loadbearing ballast may not have been considered as a significant factor in conventional rail track design. This is because the confining pressure applied on the tracks by the shoulder ballast and sleepers is small in comparison with the relatively high vertical stress. The in-situ confining pressure provided by ballast perpendicular to the rail has been estimated in the range 5–40 kPa, based on assumed coefficients of lateral earth pressure for ballast(Selig & Alva-Hurtado, 1982). The ballast layer is essentially self-supporting and is free to spread laterally owing to minimal resisting forces. The...