Geotechnical aspects of ballasted rail tracks and stabilising underlying soft soil formation

The necessity of keeping a competitive edge against other means of transportation has increased the pressure on the railway industry to improve its efficiency and decrease maintenance and infrastructure costs. A comprehensive research program was launched at the University of Wollongong (UoW), sponsored by the Australian Cooperative Research Center for Railway Engineering and Technologies to investigate various methods to stabalise tracks underlying soft soil formation. The research findings show that the bonded geogrids-geotextiles can improve the performance of ballasted tracks and the installation of prefabricated vertical drains in soft formation can reduce the preloading period significantly. According to experimental and field trial investigations it has been found that the ballast deformation and breakage can be reduced if appropriate ballast grading and track confining pressure are applied.