Bridge query Ashford to Tonbridge route

[Dixie]

Just watching a cab ride from Ashford to Tonbridge in Kent, a normal ex Southern 3rd rail electric route. One thing that struck me as a bit odd was that many of the bridges look like they have been rebuilt for electrification of the overhead variety. I have attached a photo of one. I presume that there is probably a totally unrelated reason for this, but wondering if anyone could explain.

 

[seagull]

I believe it was to do with the continental container traffic gauging as I recall it happened around the time the Channel Tunnel opened and of course well before HS1 was built.
But that might be erroneous.

 

[Dixie]

Thanks for that, I noticed that the route via Sevenoaks towards London seems to have been similarly treated.

 

[Romsey]

I believe it was to do with the continental container traffic gauging as I recall it happened around the time the Channel Tunnel opened and of course well before HS1 was built.
But that might be erroneous.

There are two classic routes across Kent which are cleared for SB1C swap bodies and W8 containers: Dollands Moor - Ashford - Maidstone East - Swanley - Shortlands Jn - Nunhead - Factory Jn - Kensington Ol - Wembley EFOC. The alternative ( diesel hauled only due to weak power supplies) is Dollands Moor - Ashford - Tonbridge - Redhill - East Croydon - Clapham Jn - Kensington Ol - Wembley EFOC. The bridge building was one part of the Channel Tunnel upgrading of Kent. Improving track quality was a major and much needed improvement and finally the upgraded power supply for Eurostar and class 92 workings.

Some bridges via Sevenoaks and Orpington / Bat and Ball were also replaced, but I suspect that was due to the structures needing repair or replacement.
Via Sevenoaks was not cleared for SB1C or W8 , but a few containers went that way and left scars on the lining of Sevenoaks tunnel.

It's almost academic these days there is so little Channel Tunnel rail freight. Much of the container and swap body traffic now runs over HS1 to and from the new terminals at Barking. What does run via the SE domestic routes is steel traffic and conforms to W6a profile.

 

[yorksrob]

Yes, I remember travelling in Kent when it was happenning. There were a lot of engineering works and publicity around "rebuilding Kent's railway".

 

[Dixie]

Thanks both of you. There's some references to the above in this document: http://igg.org.uk/rail/2-track/02track3.htm

 

[traingeek97]

Just watching a cab ride from Ashford to Tonbridge in Kent, a normal ex Southern 3rd rail electric route. One thing that struck me as a bit odd was that many of the bridges look like they have been rebuilt for electrification of the overhead variety. I have attached a photo of one. I presume that there is probably a totally unrelated reason for this, but wondering if anyone could explain.

Have you got a link to the cab ride please @Dixie?

 

[swt_passenger]

It’s a standard bridge re-construction method of the time known as a “conarch”. I think they’re still used on occasions, but many bridge rebuilds nowadays use complete flat deck beams to give maximum height clearance over the full width. There’s a few examples of conarch construction on this manufacturer’s website:

Macrete

Macrete

www.macrete.com

 

[Dixie]

Have you got a link to the cab ride please @Dixie?

Sorry, only just read your comment. It's here and is followed by two other videos that continue the trip:

They should appear automatically but if not message me and I'll post the links for those as well.

It’s a standard bridge re-construction method of the time known as a “conarch”. I think they’re still used on occasions, but many bridge rebuilds nowadays use complete flat deck beams to give maximum height clearance over the full width. There’s a few examples of conarch construction on this manufacturer’s website:

Macrete

Macrete

www.macrete.com

Thanks for that. Very interesting.

 

[Mcq]

Excellent video and comments - thank you