M4 Junction 3 to 12 Smart Motorway

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jackal
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Re: M4 Junction 3 to 12 Smart Motorway

Post by jackal » Wed Jan 15, 2020 22:21

This supplier also mentions trials on the M1 and M62:

https://navtechradar.com/stopped-vehicl ... -highways/

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Re: M4 Junction 3 to 12 Smart Motorway

Post by EpicChef » Wed Jan 15, 2020 23:02

I hope you tuned in on Monday at 9 on channel 5, because they had the documentary about the M1, of which I have taken a number of remarkable snapshots. I am impressed with the lady Marissa working in the RCC because she manages everything so professionally. The "leave motorway at next exit" symbol is used on the gantries alongside :XXXX: STOP Road closed which is exactly the sequence we need for a closure and a diversion up and over the exit slip and onto the entry slip. There are people out there who take this very seriously and we can't forget how many people like Marissa must be feeling so guilty, as she said, about trying to prevent a fatality on the motorway. This level of precise traffic management would have been impossible without the gantries, signs, signals and MS4s. The technology isn't the problem. And the people in the RCC are doing their job. It's the fact that we need a replacement to the hard shoulder that we can trust. Otherwise there won't even be a shoulder for loved ones to cry on.
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Re: M4 Junction 3 to 12 Smart Motorway

Post by hoagy_ytfc » Wed Jan 15, 2020 23:28

Jeni wrote:
Wed Jan 15, 2020 20:52
And yes, sadly, those that decide these things do put a price on a human life.

I'm not sure how else we'd evaluate which safety schemes we spend our budget on, though.

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Re: M4 Junction 3 to 12 Smart Motorway

Post by Jeni » Thu Jan 16, 2020 06:36

hoagy_ytfc wrote:
Wed Jan 15, 2020 23:28
Jeni wrote:
Wed Jan 15, 2020 20:52
And yes, sadly, those that decide these things do put a price on a human life.

I'm not sure how else we'd evaluate which safety schemes we spend our budget on, though.
I'm not arguing the rights or the wrongs, just expressing emotion to the situation.

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Re: M4 Junction 3 to 12 Smart Motorway

Post by A303Chris » Thu Jan 16, 2020 15:57

EpicChef wrote:
Tue Jan 14, 2020 16:43
They’ve made it a point not to have people moving from junctions 3-12 at 50mph. They’ll probably put in a 60 limit at least for the more advanced bits - which means people aren’t held up.
The latest newsletter from the HE says that J12 to J8/9 will be completed this summer and fully up to National Speed Limit early 2021. I take this that there will be 6 months of testing, finishing bits of and if like the M5 and M3 schemes operated at 60 mph for a few months before fully opening at NSL.
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Re: M4 Junction 3 to 12 Smart Motorway

Post by DB617 » Sat Jan 18, 2020 12:51

How long is the Huntercombe Spur bridge supposed to be down for? Seems like a really bum deal for Slough, Windsor and Maidenhead this weekend.

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Re: M4 Junction 3 to 12 Smart Motorway

Post by c2R » Mon Jan 20, 2020 17:03

I got the chance to drive the whole length of this in the daytime, for the first time in a couple of years today. The structure replacement and length of the work that's going on is certainly impressive.
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Re: M4 Junction 3 to 12 Smart Motorway

Post by Bendo » Mon Jan 20, 2020 17:10

To me it is quite simple, ALR should simply not exist without SVD. How can it be considered that 17 mins on average is an acceptable time to detect a stationary vehicle. It simply isnt.

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Re: M4 Junction 3 to 12 Smart Motorway

Post by mathmo » Mon Jan 20, 2020 21:38

Over the weekend the 50mph limit has been extended through the gap where it previously was (J5-6 and a bit each side of that). Between J5 and J6 it's still full-width lanes though so quite tedious.

Does anyone know whether J8/9-10 is still 50mph too? I haven't been that way since Christmas.

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Re: M4 Junction 3 to 12 Smart Motorway

Post by c2R » Mon Jan 20, 2020 21:58

mathmo wrote:
Mon Jan 20, 2020 21:38
Over the weekend the 50mph limit has been extended through the gap where it previously was (J5-6 and a bit each side of that). Between J5 and J6 it's still full-width lanes though so quite tedious.

Does anyone know whether J8/9-10 is still 50mph too? I haven't been that way since Christmas.
It was 50mph the whole way from 3 to 12 this afternoon.
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Re: M4 Junction 3 to 12 Smart Motorway

Post by EpicChef » Mon Jan 20, 2020 22:00

c2R wrote:
Mon Jan 20, 2020 21:58
mathmo wrote:
Mon Jan 20, 2020 21:38
Over the weekend the 50mph limit has been extended through the gap where it previously was (J5-6 and a bit each side of that). Between J5 and J6 it's still full-width lanes though so quite tedious.

Does anyone know whether J8/9-10 is still 50mph too? I haven't been that way since Christmas.
It was 50mph the whole way from 3 to 12 this afternoon.
Wow that's a lot. It may be a better idea to use M25 --> M40 --> A404 --> A404M --> M4 for those originating from M25 north of M40 who want to go west of J8/9.
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Re: M4 Junction 3 to 12 Smart Motorway

Post by c2R » Mon Jan 20, 2020 22:04

EpicChef wrote:
Mon Jan 20, 2020 22:00
c2R wrote:
Mon Jan 20, 2020 21:58
mathmo wrote:
Mon Jan 20, 2020 21:38
Over the weekend the 50mph limit has been extended through the gap where it previously was (J5-6 and a bit each side of that). Between J5 and J6 it's still full-width lanes though so quite tedious.

Does anyone know whether J8/9-10 is still 50mph too? I haven't been that way since Christmas.
It was 50mph the whole way from 3 to 12 this afternoon.
Wow that's a lot. It may be a better idea to use M25 --> M40 --> A404 --> A404M --> M4 for those originating from M25 north of M40 who want to go west of J8/9.
It depends on your origin - I was driving from Sloane Square, so the M4 was a more obvious choice than picking my way further up through London to join the A40. Similarly, traffic coming from the M25 anticlockwise probably would have a better choice taking the M3 nd then either cutting through Bracknell or taking the A303 to avoid it. That said, there wasn't a great deal of traffic mid afternoon....
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Re: M4 Junction 3 to 12 Smart Motorway

Post by A303Chris » Tue Jan 21, 2020 09:09

mathmo wrote:
Mon Jan 20, 2020 21:38
Over the weekend the 50mph limit has been extended through the gap where it previously was (J5-6 and a bit each side of that). Between J5 and J6 it's still full-width lanes though so quite tedious.

Does anyone know whether J8/9-10 is still 50mph too? I haven't been that way since Christmas.
No the whole length from J3 to J12 is 50 mph did it both ways, yesterday afternoon and late evening after going to the West End for a show and parking at Barons Court. Is this the longest temporary speed limit on a motorway ever of 32 miles.

The last newsletter said J8/9 to J12 would be completed this summer and would not revert to NSL to next year, I hoping as they did with the M3, M5 and M6 Smart schemes that at least they run it at 60mph while they test the technology.

Interesting thing about the 50mph filling the J4b to J6 gap, is that the signing is poor. The 50mph repeaters are only on the central resevere, the average speed cameras on the section have signs saying "Camera not in use" and westbound you are confronted with a roadworks end and NSL sign, just after you pass under the M25, to be followed by a 50mph in the central reserve , 300 yards later. However given the rest is all enforced 50mph, even at 12.15am, everyone was stricking at 50 to 55 mph through the entire section.

Another bug bear with the scheme is these new VMS that have appeared at the western end saying "Roadworks adding 2 minutes to your journey", well the difference between 50mph and 70mph is 21 seconds a mile, so 32 miles equates to 630 seconds (10 1/2 minutes), so the signs refer to between the junctions. Ten minutes may not sound long but on a dead road it is so tedious
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Re: M4 Junction 3 to 12 Smart Motorway

Post by exiled » Tue Jan 21, 2020 12:07

When discussing Smart Motorways in general please use the
viewtopic.php?f=1&t=39392&start=380
thread which is for the policy and practice.

Within individual schemes, the smartification of the motorway should be for that road only, such as here about the M4.

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Re: M4 Junction 3 to 12 Smart Motorway

Post by WHBM » Tue Jan 21, 2020 14:38

A303Chris wrote:
Tue Jan 21, 2020 09:09
Interesting thing about the 50mph filling the J4b to J6 gap, is that the signing is poor. The 50mph repeaters are only on the central resevere, the average speed cameras on the section have signs saying "Camera not in use" and westbound you are confronted with a roadworks end and NSL sign, just after you pass under the M25, to be followed by a 50mph in the central reserve , 300 yards later.
The set out of TM signage and temporary arrangements on this scheme is some of the worst I have seen, which I have commented on before.
Another bug bear with the scheme is these new VMS that have appeared at the western end saying "Roadworks adding 2 minutes to your journey", well the difference between 50mph and 70mph is 21 seconds a mile, so 32 miles equates to 630 seconds (10 1/2 minutes), so the signs refer to between the junctions. Ten minutes may not sound long but on a dead road it is so tedious
This is only working to absolutes. In practice on a NSL motorway 75mph is a common speed, it being treated as a general guide. On Specs-enforced 50mph limits the average I find is rarely more than 45mph. So that's another 15 minutes on this section. And as "your journey" for most people is a round trip within a day, it's actually another 30 minutes.

Now if work was actually in progress on the entire section at once, it might have merit. But it's not.

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Re: M4 Junction 3 to 12 Smart Motorway

Post by mathmo » Tue Jan 21, 2020 18:19

J6 to the previous start of speed limit between J5 and J4b was back to NSL this morning! Someone must have made a mistake.

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Re: M4 Junction 3 to 12 Smart Motorway

Post by Bryn666 » Tue Jan 21, 2020 20:17

I'm under the impression that complaints by the police to HE have been frequent about poor signing so perhaps they've been told to put it back to NSL until they sort it out.

See also the M60 farce where TTM contractors made a complete testicles of a simple job.
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Re: M4 Junction 3 to 12 Smart Motorway

Post by A303Chris » Mon Jan 27, 2020 15:32

Update below from the HE with regards the next full weekend closure which will finish early on the Sunday given the rugby at Twickenham, forget the thousands going to Stamford Bridge on the Saturday. It also says regular weekend closures between April and November, brilliant on the main route to the busiest international airport in the world, during the holiday season.
21-23 February - full weekend closure between junction 4b and 5
We will demolish Old Slade Lane bridge near junction 4b during the weekend of Friday 21 (8pm) to Sunday 23 (6am) February 2020. The work will be complete early on the Sunday morning in order to reopen the motorway ahead of the Six Nations match at Twickenham that afternoon.
The diversion route for motorway traffic during this weekend has been agreed with local authorities and will use the M25, A3113, A3044 and A4.
There will be regular full weekend closures of the M4 throughout this year, mostly taking place between April and November. You can find out more in our bulletins and on our websites.
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Re: M4 Junction 3 to 12 Smart Motorway

Post by BOH » Tue Jan 28, 2020 13:49

A303Chris wrote:
Mon Jan 27, 2020 15:32
Update below from the HE with regards the next full weekend closure which will finish early on the Sunday given the rugby at Twickenham, forget the thousands going to Stamford Bridge on the Saturday. It also says regular weekend closures between April and November, brilliant on the main route to the busiest international airport in the world, during the holiday season.
I believe LHR has lost that crown now, about 3-4 years ago IIRC. I think is now DXB

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Re: M4 Junction 3 to 12 Smart Motorway

Post by Bendo » Tue Jan 28, 2020 16:32

BOH wrote:
Tue Jan 28, 2020 13:49
A303Chris wrote:
Mon Jan 27, 2020 15:32
Update below from the HE with regards the next full weekend closure which will finish early on the Sunday given the rugby at Twickenham, forget the thousands going to Stamford Bridge on the Saturday. It also says regular weekend closures between April and November, brilliant on the main route to the busiest international airport in the world, during the holiday season.
I believe LHR has lost that crown now, about 3-4 years ago IIRC. I think is now DXB
Since the year 2000 it has been Hartsfield–Jackson Atlanta International Airport. LHR is 7.

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