1. Analysis of capacity on double-track railway lines
Olov Lindfeldt
February 2008

2. Disposition Introduction – freight capacity question TVEM (model)
Infrastructure modeling
Application
- Three-pattern case
Conclusions

3. Freight capacity question
What is the capacity for freight traffic on existing lines if high speed lines are constructed?
It depends on the timetable!
Ways to find the timetable for 2050:
Assume one
Make more general assumptions an generate a large number of timetables
Develop an algorithm that generates timetables and evaluate freight capacity as a distribution…
Disregard disturbances (delays)

4. Freight capacity question
What is the capacity for freight traffic on existing lines if high speed lines are constructed?
It depends on the timetable!
Ways to find the timetable for 2050:
Assume one
Make more general assumptions an generate a large number of timetables
Develop an algorithm that generates timetables and evaluate freight capacity as a distribution…
Disregard disturbances (delays)

5. Freight capacity question
What is the capacity for freight traffic on existing lines if high speed lines are constructed?
It depends on the timetable!
Ways to find the timetable for 2050:
Assume one
Make more general assumptions and generate a large number of timetables
Develop an algorithm that generates timetables and evaluate freight capacity as a distribution…
Disregard disturbances (delays)

6. Freight capacity question
What is the capacity for freight traffic on existing lines if high speed lines are constructed?
It depends on the timetable!
Ways to find the timetable for 2050:
Assume one
Make more general assumptions and generate a large number of timetables
Develop an algorithm that generates timetables and evaluate freight capacity as a distribution…
Disregard disturbances (delays)

7. Research view
Aim
How do the infrastructure and the timetable affect capacity?
Method
Combinatorial analysis of infrastructure designs and timetable structures.
 TVEM: Timetable Variant Evaluation Model

8. TVEM: Assumptions Passenger traffic operated with a periodic timetable
Train patterns
All patterns are scheduled according to a priority order.
A train with higher priority is never given scheduled delay for a train with lower priority.

9. TVEM: Structure

10. TVEM: Variables
Run times between overtaking stations (infrastructure + vehicle)
Deceleration and acceleration supplements (for overtaking situations)
Regular stops
Track dispositions at stations
Frequency of service
Scheduling order

11. TVEM: Calculation scheme
Periodic timetable  train patterns
Scheduling order for train patterns
Time step: 1 minute
Last pattern: as many freight trains as possible

12. Infrastructure modelling (1/2)
Real distribution for inter-station distance.
Fitted Weibull distribution (M-L).
Mean: 22,7 km Std: 109 km2.

13. Infrastructure modelling (2/2)
Effect of additional overtaking stations?
Halve the greatest distance repeatedly.  relationship between parameters

14. Application: Three-pattern case High-speed, regional and freight trains
Mean number of trains (capacity):
Two speed combinations
- 160/115 km/h (dotted)
- 210/160 km/h (solid)
Two infrastructure layouts. Inter-station distance:
- mean 22 km (lower)
- mean 17 km (upper)

15. Conclusions Combinatorial / deterministic approach  TVEM
Infrastructure treated as a variable. Modeled stochastically (replications)
Regular passenger timetable  train pattern  combinatorial timetable analysis
Evaluation: mean capacity, variance caused by:
Infrastructure
Timetable

16. Thank You for the attention!
Number of freight trains/h