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Other Hondas & General Topics => Off Topic (Non-Honda) => Topic started by: Jocko on September 10, 2017, 03:52:42 PM

Title: Queensferry Crossing.
Post by: Jocko on September 10, 2017, 03:52:42 PM
I used the new Queensferry Crossing in anger yesterday and what a wonderful piece of engineering. The problem is that everyone and their dog are visiting it and the queues are horrendous. It was fine going over it in the morning, busy but moving steadily, but on my return, at lunch time, the queues had formed. I decided it was better to continue up river and cross with the Kincardine bridge. As I drove back through Fife I crossed the M90 and the southbound queue stretched 9 miles - both lanes, pretty much stationary.
According to the Traffic Scotland Twitter page, it is the same today, and it is raining, bleak and a day for staying at home. Hopefully, for people who need to use the bridge in anger, the novelty will soon wear off.
Title: Re: Queensferry Crossing.
Post by: pb82gh3 on September 10, 2017, 08:40:47 PM
There's a fantastic animation showing this incredible build here
Title: Re: Queensferry Crossing.
Post by: Jocko on September 10, 2017, 09:51:55 PM
That is superb. Thank you. I watched it going up but never realised the intricacy of it all.
Title: Re: Queensferry Crossing.
Post by: culzean on September 12, 2017, 08:27:44 PM
One sad part of the new bridge........

149 segments of bridge deck, each of which is 12 metres (39 ft) long and 40 metres (130 ft) wide, were constructed in China and Spain

(1.8 kilometres)

The builders were a consortium of Spanish, German, American and token British company (Morrison Construction / Galliford who probably did some of the roads LOL ).

Engineering has been a dirty word in UK for many decades,  produced too much carbon apparently (unlike the financial sector which is low carbon apparently) - so we asked the Chinese and Spanish to do the 'dirty' work and have the carbon in their countries while we just put the bolts in and paint stuff - I am ashamed that we cannot even make our own bridges any more.
Title: Re: Queensferry Crossing.
Post by: Jocko on October 02, 2017, 09:46:06 AM
Looks like the new bridge has passed its first "trial by combat". With winds currently a steady 50 mph and gusts to 70 mph there has been no need for restrictions, other than the blanket 40 mph currently in force 24/7. The wind deflectors must be doing their stuff, despite the fact they rather spoil the view from the bridge. Mind you, no view means no rubbernecking tourists.
Title: Re: Queensferry Crossing.
Post by: Jocko on October 28, 2017, 08:49:00 PM
Once again a real windy day and the Forth Road Bridge, which is now open to service buses, was closed to double deckers. However, the Queensferry Crossing had no restrictions other than the 40 mph average speed cameras. That should be lifted shortly, and not long after that it will be uprated to full motorway status, albeit with Smart Speed Limits.
Title: Re: Queensferry Crossing.
Post by: Jocko on November 06, 2017, 07:19:52 AM
That's them finally raised the speed limit on the new bridge to 50 mph. Hopefully it will soon be up to full motorway and 70 mph before too long. There is Intelligent Traffic Management in place, so smart speed limit signs can adjust the limit in force, depending on traffic conditions.
Title: Re: Queensferry Crossing.
Post by: Jocko on November 14, 2017, 01:34:05 PM
Made my first crossing of QFC in the dark this morning. Unlike the FRB, it is not lit, with only lights on the approach viaducts. However, these lights are like bright bulkhead lights at eye level, and are most distracting. It is like driving towards a stream of approaching cars, all with their headlights on. Not great road safety design! You can see the lights, every six feet below the rail, in this photograph.
Title: Re: Queensferry Crossing.
Post by: culzean on November 14, 2017, 04:13:54 PM
They have to warn people with epilepsy when they have flashing images on TV in case it triggers a fit,  even sunlight flashing through trees on a road can do it so surely those lights on the new bridge are a hazard for certain people.
Title: Re: Queensferry Crossing.
Post by: John Ratsey on November 14, 2017, 06:17:56 PM
Perhaps someone decided that changing the bulbs on proper streetlights would be too much hassle (not that LED lamps would need much maintenance) or maybe the worry was the extra wind drag caused by the poles. However, it wouldn't have been too challenging to have installed lights near the top of the wind barriers and shaded such that they illuminate the road without annoying the drivers.
Title: Re: Queensferry Crossing.
Post by: Jocko on November 14, 2017, 07:10:59 PM
The lights don't flash as you pass them, there in nothing between you and the light, but they should be baffled from the driver's direct view. they do that with railway signals near roads, and there is station beside the M8 where all the bright lights have baffles so drivers don't get dazzled/distracted.
There is no need for the lights on the QFC. There is nothing on the motorway either end, and none between the north and south towers, so why the have them for a couple of hundred yard each end is anyone's guess.
Title: Re: Queensferry Crossing.
Post by: Jocko on November 17, 2017, 03:11:46 PM
Received the following email from Forth Crossing Bridge Constructors.

Lighting of the highway is not required over the full length of the bridge but is needed at each end to fulfil the requirement to light the carriageway within a safe distance from the start or finish of the slip road merge. This lighting on the bridge has been provided by low height lighting bollards for the following reasons:
Minimum risk to maintenance workers in the upkeep of the lanterns as there is no working at height from mobile elevated working platforms required to change or clean lanterns.
Reduction in light pollution and hence minimum intrusion on adjacent properties and World Heritage views.
The design of the lighting has recognised the apparent flicker that would be observed by vehicle occupants travelling past these lights at design road speeds. There is guidance within the British Standards that provides limits on flicker that are to be avoided to prevent visual discomfort. The design complies with these requirements in particular the duration over which the occupant observes flicker and frequency of the light pulses. The design and the arrangement has been reviewed by the independent Road Safety Auditor.
Additionally, the design was assessed against other international guidance and also clinical research papers into the frequency ranges that present a risk of photosensitive epileptic seizures; and found to be satisfactory. When travelling at 70mph or less, the frequency of flicker is outside the risk envelope defined in the studies. Further mitigation exists in that the light is directed downward and the flicker is only projecting into the periphery of vision of a driver. An existing installation was inspected to assess the impact of flicker and was considered to be less obtrusive than dimmed headlights in oncoming traffic on single carriageway roads.
Currently the brightness of the lighting cannot be controlled and they are at the brightest setting.  In the coming months, an Intelligent Light Control System will be installed which will be able to dim the lights taking into account local ambient light levels.