Page 285 - 360.revista de Alta Velocidad - Nº 5

Reducing High-Speed Rail Costs by Combined Double-Single Tracks

The design and management of an ADST line is complex, because it requires:

1. Deciding which segments should be constructed in single track and which in double track.

2. Satisfying the safety and timetable constraints of the different services with the aim of
obtaining small travel times when we have a single track in some segments.

3. Minimizing costs and travel times and optimize the infrastructure usage.
4. Obtaining all rail timetables of the whole network.

Due to the complexity of the problem, the use of an optimization program is necessary in order
to satisfy all the imposed safety and service conditions.

This paper aims to introduce two case studies that clearly show the benefits of using this
methodology. Finally, some conclusions will be drawn.

2. Case studies

The case studies used in this paper correspond to the corridors Santander-Bilbao and
VitoriaZaragoza (Spain). For each case, the following procedure will be applied: (1) a diagnosis
of the current situation will be described; (2) the inputs and outputs of the program will be
outlined; and (3) the adopted solution will be justified by carrying out a multi-criteria analysis.

2.1 Santander-Bilbao case

2.1.1 Current line

The existing rail line between the cities of Santander and Bilbao (see Figure 1 ), in northern
Spain, is obsolete compared to modern transportation. Due to the inefficiency of this means of
transport, displacements between these two cities are mainly done by private vehicle or bus.

Figure 1. Actual road and railway connections between Santander and Bilbao.

The population of the metropolitan areas of these two capital cities combined comes to more
than one million citizens, being Bilbao the most populated one.
This High speed railway line could be part of a possible 'Cantabrian Corridor', from Galicia to
the French border, improving connections with Europe. This fact addresses the significance of
this infrastructure.

International Congress on High-speed Rail: Technologies and Long Term Impacts - Ciudad Real (Spain) - 25th anniversary Madrid-Sevilla corridor 283