Rail Analysis India June Digital Magazine 2018 - Page 36

Article | 37 Placing a layer of Techgrid PP within sub ballast above geotextile. The ballast layer for example is subjected to repeated dynamic and cyclic loadings, as well as elevated temperature. Project - Stabilization of Tracks at Kharagpur Junction for platform 1 & 3 Site Condition – After visiting the site, it was observed that Track bed was in distressed condition, there was water leakage at some locations on the track bed resulting in moist condition. Track bed settlement was also observed at multiple locations. Techgrid PP act as a working platform underlying over weak soil by supporting the load of construction equipment, preventing excessive deformation of subgrade and facilitating proper compaction of granular layer /sub ballast. Techgrid PP improves the performance of ballast and sub ballast /blanket layers of railway track bed. Solution – After a careful evaluation of the project requirements and site conditions, given solution is that the existing ballast should be removed and redone using PP Biaxial Geogrid and Nonwoven Geotextile. The proposed section is as follows: Placing a geotextile on the interface of sub-ballast and the sub base. The geotextile gives a tensioned member effect and will act as a separator to separate the mixing of the large base particles with the sub-base. This will also give effective load distribution. The pumping of fines from subgrade to sub- base is reduced. www.railanalysis.com www.railanalysis.com