The Use of Bituminous Subballast on Future High-Speed Lines in Spain: Structural Design and Economical Impact
P. F. Teixeira**/P. A. Ferreira**/A. López Pita*/C. Casas*/A. Bachiller*
International Journal of Railway, vol. 2, no. 1, pp.1-7, 2009
Abstract : The development of structural solutions for high-speed or very high-speed tracks that minimize total life cycle costs of
the system is a key issue to improve the operational profitability of new investments. In opposition to conventional ballasted
tracks, slab track solutions can be a cost-effective solution, but only in the cases where the benefits due to the
increase in track availability and the reduction of track maintenance offsets its much higher construction costs. In the
cases where such investment is not feasible, it is worth to evaluate possible structural improvements to ballasted track
that allow reducing its maintenance needs without increasing too much its construction costs. This paper evaluates the
design requirements and the impact of improving conventional high-speed ballasted tracks by using a bituminous subballast
layer. It is divided into two main parts: first the design requirements of the structural solutions with bituminous
subballast and its possible benefits on high-speed track deterioration, and secondly the evaluation of the economic
impact, in terms of construction costs, of using this structural solution material in future Spanish high-speed lines.
Keyword : Slab Track, Ballasted Track, Bituminous Subballast |