die belebende Bedenkung

HS2 irresilience

with 3 comments

The University of Connecticut document ‘Network Vulnerability and High-Speed Rail‘ presented by Nicholas Lownes, noted that

* The vulnerability of a transportation network is strongly correlated with the ability of the network to withstand shocks and disruptions.
* High-volume edges with limited alternative paths represent obvious system vulnerabilities.

The design of HS2 makes it highly vulnerable to disruption. It would be connected to the legacy rail system, but its preferred European-interoperable GC gauge rolling stock would not generally be able to interoperate on British track. The outcome would be that HS2 is exposed to the perturbations from classic rail, but is not able to use those connections to effectively re-route traffic in response to disruption on its own line, or on some other portion of the legacy network.

3 Responses

Subscribe to comments with RSS.

  1. You state that the design of HS2 makes it highly vulnerable to disruption. Arguably the reverse is the case: HS2 would be operated on purpose-built infrastructure, with southbound and northbound lines adequately separated so that one line could continue operations in the event of a blockage of the opposite line. All junctions are grade-separated and trains have identical power and braking characteristics. There are no intermediate stations on the busiest section of the route. Thus many of the potential causes of disruption are eliminated.

    There is a risk that delays on the existing rail network could be imported onto HS2 on those “Classic Compatible” trains running beyond the ends of the HS2 network. However these are also the types of trains which could be diverted to use the existing network in the unlikely event of a route blockage on HS2.


    September 18, 2011 at 7:44 pm

    • I’m sure that lines on the wide former Great Western broad gauge system have been simultaneously blocked in both directions, through incidents such as floods or landslides. So wider separation of tracks may turn out not to be ‘adequate’.

      It’s not possible to determine how likely route blockages on the HS2 trunk would be. The intensive use planned for it would demand equally intensive maintenance, carried out mainly at night. In the event of such work over-running, there would be a de facto blockage.

      Whether the two types of HS2 train would have identical power and braking characteristics, I have no idea. But the captive fleet allocated for the Birmingham – London line wouldn’t be able to use the existing network, and there’s no sign of a planned connection between legacy and HS2 lines in the city of Birmingham. The issue would be amplified in a larger GC gauge network.


      September 18, 2011 at 11:17 pm

  2. […] Ltd’s Y network concept has massive built-in irresilience, with all premier intercity trains from the Midlands and North having to be fed down one track from […]

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: