Frequency of trains on high speed lines

[PTR 444]

With HS2 designed to take up to 18 trains per hour in each direction, it will become the most heavily trafficked high speed railway in geographical Europe. On the continent however, most high speed lines don’t even see half as many trains as that. I’m wondering what the minimum frequency for a proposed 250+km/h high speed railway corridor would be to make it viable to build in the first place, and whether most lines even reach these projections upon opening? I understand that the minimum viable frequency will vary for each line depending on speed, length, terrain and environmental mitigations, but as a general figure what would you say is the bare minimum frequency for a high speed railway?

 

[hexagon789]

Isn't Perpignan to Barcelona something daft like two trains each way per day? Over a 176km (109mi) high-speed line.

 

[30907]

Isn't Perpignan to Barcelona something daft like two trains each way per day? Over a 176km (109mi) high-speed line.

Going up to 4 when RENFE resume running. The Nimes/Montpellier bypass isn't over-busy either - but both were built for mixed use.

Most of the HSLs in Germany are much less busy than the French or Italian ones (ignoring odd spurs) - the Halle/Leipzig-Erfurt-Bamberg-Nuremburg route is typically 3tph North of Erfurt and below 2tph to the South. Even Cologne Frankfurt is basically 3tph.

 

[stuu]

Depends what you mean by viable. Different countries have different methodologies - Spain's network is based on the principle that all provincial capitals should be 4 hours from Madrid, and 6 from Barcelona for example. Other countries are less extreme in using their infrastructure for national cohesion but it's still a greater factor in many places than in the UK - Italy is spending billions on rail improvements in Sicily right now for example