On Wed, 19 Jun 2019 12:43:48 +0100, "Clive D.W. Feather"
wrote:

In article , Roland Perry
writes
The only disruption will come at the end, when the traffic is diverted to
the new route. My guess is that the northbound traffic will be moved first,
with a few weeks of lane 1 closures required while they connect the new to
the old carriageways, then an overnight closure for the final switch to be
made. The same procedure would then be followed a few months later to
divert the southbound carriageway to the new alignment.

The amount of work you would be expecting them to do "overnight" beggars
belief.

I disagree.

Build the two new carriageways. At each end, cut them off very close to
the edge of northbound lane 1 (there's no hard shoulder, right? if there
is, adjust description accordingly).

Cone off northbound lane 1. Spend a week or two filling in the narrow
gap between the old and new northbounds at each end.

Not sure that you even need a closure to switch over. Simply move all
the cones.

Repeat for the southbound (though this time you're closing lane 4).


Yes, that's what I'm expecting.

"Recliner" wrote in message
...
On Wed, 19 Jun 2019 12:43:48 +0100, "Clive D.W. Feather"
wrote:

In article , Roland Perry
writes
The only disruption will come at the end, when the traffic is diverted
to
the new route. My guess is that the northbound traffic will be moved
first,
with a few weeks of lane 1 closures required while they connect the new
to
the old carriageways, then an overnight closure for the final switch to
be
made. The same procedure would then be followed a few months later to
divert the southbound carriageway to the new alignment.

The amount of work you would be expecting them to do "overnight" beggars
belief.

I disagree.

Build the two new carriageways. At each end, cut them off very close to
the edge of northbound lane 1 (there's no hard shoulder, right? if there
is, adjust description accordingly).

Cone off northbound lane 1. Spend a week or two filling in the narrow
gap between the old and new northbounds at each end.

Not sure that you even need a closure to switch over. Simply move all
the cones.

Repeat for the southbound (though this time you're closing lane 4).


Yes, that's what I'm expecting.

I have never in my life seen construction companies do this

even when the new road is well away from the old route

It costs millions extra to do it that way

tim

tim... wrote:


"Recliner" wrote in message
...
On Wed, 19 Jun 2019 12:43:48 +0100, "Clive D.W. Feather"
wrote:

In article , Roland Perry
writes
The only disruption will come at the end, when the traffic is diverted
to
the new route. My guess is that the northbound traffic will be moved
first,
with a few weeks of lane 1 closures required while they connect the new
to
the old carriageways, then an overnight closure for the final switch to
be
made. The same procedure would then be followed a few months later to
divert the southbound carriageway to the new alignment.

The amount of work you would be expecting them to do "overnight" beggars
belief.

I disagree.

Build the two new carriageways. At each end, cut them off very close to
the edge of northbound lane 1 (there's no hard shoulder, right? if there
is, adjust description accordingly).

Cone off northbound lane 1. Spend a week or two filling in the narrow
gap between the old and new northbounds at each end.

Not sure that you even need a closure to switch over. Simply move all
the cones.

Repeat for the southbound (though this time you're closing lane 4).


Yes, that's what I'm expecting.

I have never in my life seen construction companies do this

even when the new road is well away from the old route

It costs millions extra to do it that way

Why would it cost any extra? You have a completely segregated work site to
the west of the existing road, to build the new, lowered carriageways, with
runway and taxiway bridges. This might take 2-3 years, and won't affect the
existing motorway, except for a few lane closures while a safety wall is
built between the existing northbound carriageway and the work site.

When the new carriageway is ready, you need to close lane 1 of the old
northbound carriageway for a few weeks while the physical connection of the
road surfaces is made, and then an overnight closure for first the M4-bound
traffic to be diverted, and then again when the through traffic is
switched. A few months later, a similar process is used to connect the
southbound.

It won't be nearly as disruptive as when the M25 was widened to 12 lanes in
the area.

"Recliner" wrote in message
...
tim... wrote:


"Recliner" wrote in message
...
On Wed, 19 Jun 2019 12:43:48 +0100, "Clive D.W. Feather"
wrote:

In article , Roland Perry
writes
The only disruption will come at the end, when the traffic is
diverted
to
the new route. My guess is that the northbound traffic will be moved
first,
with a few weeks of lane 1 closures required while they connect the
new
to
the old carriageways, then an overnight closure for the final switch
to
be
made. The same procedure would then be followed a few months later to
divert the southbound carriageway to the new alignment.

The amount of work you would be expecting them to do "overnight"
beggars
belief.

I disagree.

Build the two new carriageways. At each end, cut them off very close to
the edge of northbound lane 1 (there's no hard shoulder, right? if
there
is, adjust description accordingly).

Cone off northbound lane 1. Spend a week or two filling in the narrow
gap between the old and new northbounds at each end.

Not sure that you even need a closure to switch over. Simply move all
the cones.

Repeat for the southbound (though this time you're closing lane 4).


Yes, that's what I'm expecting.

I have never in my life seen construction companies do this

even when the new road is well away from the old route

It costs millions extra to do it that way

Why would it cost any extra?

because you have to build a "throw away" access road to the new build road.

The alternative of accessing via the current road is "free" but causes some
of that road to need closing

tim... wrote:


"Recliner" wrote in message
...
tim... wrote:


"Recliner" wrote in message
...
On Wed, 19 Jun 2019 12:43:48 +0100, "Clive D.W. Feather"
wrote:

In article , Roland Perry
writes
The only disruption will come at the end, when the traffic is
diverted
to
the new route. My guess is that the northbound traffic will be moved
first,
with a few weeks of lane 1 closures required while they connect the
new
to
the old carriageways, then an overnight closure for the final switch
to
be
made. The same procedure would then be followed a few months later to
divert the southbound carriageway to the new alignment.

The amount of work you would be expecting them to do "overnight"
beggars
belief.

I disagree.

Build the two new carriageways. At each end, cut them off very close to
the edge of northbound lane 1 (there's no hard shoulder, right? if
there
is, adjust description accordingly).

Cone off northbound lane 1. Spend a week or two filling in the narrow
gap between the old and new northbounds at each end.

Not sure that you even need a closure to switch over. Simply move all
the cones.

Repeat for the southbound (though this time you're closing lane 4).


Yes, that's what I'm expecting.

I have never in my life seen construction companies do this

even when the new road is well away from the old route

It costs millions extra to do it that way

Why would it cost any extra?

because you have to build a "throw away" access road to the new build road.

I take it you've never looked at a map of the area, or even Google Maps?


The alternative of accessing via the current road is "free" but causes some
of that road to need closing

There are plenty of other existing roads, including the A4, they can use
for access to the work sites.

tim... wrote:


"Recliner" wrote in message
...
tim... wrote:


"Recliner" wrote in message
...
On Wed, 19 Jun 2019 12:43:48 +0100, "Clive D.W. Feather"
wrote:

In article , Roland Perry
writes
The only disruption will come at the end, when the traffic is
diverted
to
the new route. My guess is that the northbound traffic will be moved
first,
with a few weeks of lane 1 closures required while they connect the
new
to
the old carriageways, then an overnight closure for the final switch
to
be
made. The same procedure would then be followed a few months later to
divert the southbound carriageway to the new alignment.

The amount of work you would be expecting them to do "overnight"
beggars
belief.

I disagree.

Build the two new carriageways. At each end, cut them off very close to
the edge of northbound lane 1 (there's no hard shoulder, right? if
there
is, adjust description accordingly).

Cone off northbound lane 1. Spend a week or two filling in the narrow
gap between the old and new northbounds at each end.

Not sure that you even need a closure to switch over. Simply move all
the cones.

Repeat for the southbound (though this time you're closing lane 4).


Yes, that's what I'm expecting.

I have never in my life seen construction companies do this

even when the new road is well away from the old route

It costs millions extra to do it that way

Why would it cost any extra?

because you have to build a "throw away" access road to the new build road.

I take it you've never looked at a map of the area, or even Google Maps?


The alternative of accessing via the current road is "free" but causes some
of that road to need closing

There are plenty of other existing roads, including the A4, they can use
for access to the work sites.

In article , tim...
writes
I have never in my life seen construction companies do this
even when the new road is well away from the old route
It costs millions extra to do it that way

Come and look at the A14 rebuild between Girton and Swavesey. It's being
done in a similar way.

--
Clive D.W. Feather

In message , at 21:07:58 on Wed, 19 Jun
2019, Clive D.W. Feather remarked:
I have never in my life seen construction companies do this
even when the new road is well away from the old route
It costs millions extra to do it that way

Come and look at the A14 rebuild between Girton and Swavesey. It's being
done in a similar way.

And there's only disruption to the through traffic for two isolated
overnight periods (while they switch some virtual points)?

You have got-to-be-joking.
--
Roland Perry

In article , Roland Perry
writes
I have never in my life seen construction companies do this
even when the new road is well away from the old route
It costs millions extra to do it that way

Come and look at the A14 rebuild between Girton and Swavesey. It's being
done in a similar way.

And there's only disruption to the through traffic for two isolated
overnight periods (while they switch some virtual points)?

You have got-to-be-joking.

Let's see when it happens.

At the moment, the next disruption is a closure this weekend to demolish
what's left of the old Bar Hill flyover. Closures for this sort of
thing, or installing gantries, seem to be more disruptive than switching
the alignment.

--
Clive D.W. Feather

In message , at 21:59:12 on Wed, 19 Jun
2019, Clive D.W. Feather remarked:
In article , Roland Perry
writes
I have never in my life seen construction companies do this
even when the new road is well away from the old route
It costs millions extra to do it that way

Come and look at the A14 rebuild between Girton and Swavesey. It's being
done in a similar way.

And there's only disruption to the through traffic for two isolated
overnight periods (while they switch some virtual points)?

You have got-to-be-joking.

Let's see when it happens.

At the moment, the next disruption is a closure this weekend to demolish
what's left of the old Bar Hill flyover. Closures for this sort of
thing, or installing gantries, seem to be more disruptive than switching
the alignment.

Today I had the [dis]pleasure of driving the Girton to Milton section
again, and it's not noticeably further on than six months ago. Lots of
weaving contra-flow lanes, single in places, through traffic down to
30mph, and masses of work to do to even restore the original alignment -
let alone switch people from one free-flowing dual carriageway to
another with a set of overnight 'points'.
--
Roland Perry