Network Rail's Signalling standards

[whole diary]

[Trowres]

Here's a photo showing the Newport Area Resignalling in progress. The left-hand gantry is from the 1962 resignalling,  being replaced by the larger version on the right.



I don't know how much this gantry contributes to the ^150m stated cost of the resignalling (South Wales total comes to ^400m unless you know otherwise). There are other similarly chunky structures. Perhaps someone in the know could explain
a) why two ladders are necessary on the new structure
b) why it's mounted on such enormous concrete blocks?

I believe the scheme was designed by a proud private sector company. I wonder what requirements were in their brief?

[eightf48544]

Even worse I believe the new gantry is not high enough to sling the wires.

It looks as if it has been built to withstand a Scale 8 Earthquake or an HST^▸ (High Speed Train (Inter City class 43 125 units)) derailing and hitting it.

[smokey]

Here's a photo showing the Newport Area Resignalling in progress. The left-hand gantry is from the 1962 resignalling,  being replaced by the larger version on the r

I don't know how much this gantry contributes to the ^150m stated cost of the resignalling (South Wales total comes to ^400m unless you know otherwise). There are other similarly chunky structures. Perhaps someone in the know could explain
a) why two ladders are necessary on the new structure
b) why it's mounted on such enormous concrete blocks?

I believe the scheme was designed by a proud private sector company. I wonder what requirements were in their brief?

PROFIT PROFIT PROFIT oh and PROFIT 

[grahame]

It looks rather over-engineered, doesn't it?    I'm going to work on an educated guess that the new structure was more expensive to build in real terms that the old one, and suggest that this is a good illustration of why costs have risen so rapidly and dramatically in the rail industry.

Were there any problems with the 1962 gantry during its 50 years?  Did it wear out and need replacing?  Vibrate in the high wind so that the signals could not be seen?  Suffer congestion as lots of people all wanted to get onto it at the same time?  Did anyone accidentally fall off it?   If the answer to all of these is "no" then perhaps it would have been logical and cheaper to replace like for like?

[IndustryInsider]

From the perspective of the picture it looks like all you'd have to do to thwart the anti-climb cover to the base of the steps is to climb up onto that massive concrete block.

[Electric train]

Trust me that is a small signal gantry the ones installed on the Colchester / Clapton scheme are enormous.

There are a number of things that contribute to the design, the weight of the installed equipment, the wind loading on the equipment and the structure, there has to be an allowance made to with stand the weight of as many average men that could possibly stand on the platform then add a % The hight is to allow clearance for OHLE^▸ (Over-Head Line Equipment (electrification via catenary)) and possibly sighting distance.  The foundations will be calculated from the above data also possibly the surface size indicates they my be gravity foundations hence they are not very deep

2 ladders I suspect that has something to do with confined space working allowing for an escape route for staff working on the gantry

Oh and Signaling projects always go over budget