This paper highlights recent field studies at Emperor Alexander I St. Petersburg State Transport University, which helped to quantify the geosynthetics reinforcement performance in railway ballast. The rolling stock causes oscillations of track superstructure, which show up in the form of noise and vibration. The increase in loads and speeds of trains leads to a significant increase of dynamic vibra-tion effects on the roadbed. Because of this exposure the intensity of uneven residual deformation accu-mulation of the railway track increases. It affects not only on the roadbed, but also on constructions of buildings and construction.
Technologies for subgrade top reinforcing are widely used during the lines reconstruction. They allow guaranteeing the operational reliability of subgrade working area. These works are performed in complex with track repairs by the ballast cleaning machines of a new generation. These machines allow using new specialized geosynthetics which are geogrids and geocells.
Field tests were conducted on the railway section to assess the reinforcement effect on the superstructure. Geosynthetics were placed on the top of subgrade during track repair on the depth of 40 cm below the sleeper pad.
Previous studies have mostly focused on the deformation characteristics of soils, reinforced by geosyn-thetics. However, it is necessary to know the vibration level under moving load to determine their influ-ence on the bearing capacity of ballast and subgrade.
The paper describes recent research efforts in field studies, which helped to identify the geosynthetics in-fluence on substructure vibration reduction.