OT - impressive bit of civil engineering - update

I thought it was for access to a large new green-belt town ,not yet built.

Yes.

Probably as part of creating "Solent City" (the building over over any green land in south central Hampshire form Portsmouth to Southampton - and probably up to Winchester), Welborne Garden Village will be built north of Fareham. This will have 6000 new homes.

At present the only access is by the single carriageway A32 (Wickham Road), and this runs to the M27 at J10, which is a restricted access junction. The exit from the A32 is only to the eastbound side of the M27, and the exit from the M27 to the A32 is only from the westbound side. The new junction will give J10 full access, and a new road for Welborne (who thought of that name?!). Oddly, the exit from the current A32 to the eastbound M27 will be retained, but the current exit from the M27 to the A32 will be removed and become part of the new junction. A somewhat stylised view can be seen here:

Before Christmas dinner? Or after?

In message <10iori0$3hf4p$ snipped-for-privacy@dont-email.me, at 09:47:27 on Sat, 27 Dec

A timelapse of the M27 box-slide appeared in my Facebook feed just now. From ITV.com/news

While the slide took just 19hrs, the road is closed for 10 days.

Indian or African too ?? :-)

But what was that structure actually sliding on, the sub-soil ??.

There was no time to pour a nice level slab of concrete in that time window, so presumably the 'box' has a solid concrete bottom as well as sides and a 'roof' so that it became its own foundation.

Yes. I read somewhere that it is to provide access to a massive new housing development and the developers are ?paying for the new underpass.

Wouldn't surprise me if that drags on . . .

I think bot.Now my str8uctural engineering is weak, but I would imagine at the least a meter plus of MOT Type one sub base, well compacted, to keep the foundation dry and spread the load to the sub soil, then that would be blinded with sand probably before the clay was poured on top to make the slideway.

The bentonite slurry.

The article mentions other materials you could use, which would be less appreciated by the staff. The bentonite might be cheaper to mix up.

Yanking on it, encourages sliding over the bentonite.

There were pipes fitted on the workpiece, to allow pumping of slurry underneath.

A Google on the bentonite, shows it has multiple applications in construction and installation.

And slides from things similar to that, happen in nature. It does not take any sort of significant slope at all, to have a landslide. All it takes is the right kind of soil, plus a couple inches of rain to set it off. When an area is known for this, you must get a geotechnical survey before building. There has been more than one subdivision here, where the people either could not move in, or they were forced to move out, when soil conditions under the ground were accidentally exposed during sewer work and someone recognized this was the wrong kind of geo for homes to be built on. (Or at least, not the right kind of construction technique was used.)

So while these materials are great for The Slide, they can also have consequences when you build things on the ground. Some unintentional sliding can take place, right after a generous rain.

Paul

So they could have used custard then ? :-).

Would taste-the-Difference slide faster ??

The news this morning is that the motorway will reopen at 0400 tomorrow morning - 24 hours early.

That's pretty good going, no doubt helped by perfect weather conditions as there has been no rain since 21 December.

Perhaps there will eventually be a time-lapse video of the whole thing.

In message <10j7vqj$8774$ snipped-for-privacy@dont-email.me, Jeff Layman snipped-for-privacy@invalid.invalid writes

Congratulations to all concerned.

A full timelapse would be interesting, but I suspect for most people, the interest would be the new span being slid into space, rather than the earth moving before and after,

Adrian

I think those are what are generally called "Strand Jacks", often used for heavy lifting or moving.

Chris

Quite possibly, searching for that term seems to show them commonly used vertically for lifting, but no reason against using them horizontally for pulling ...

Called tendon jacks when I was in the civil engineering world, only for pulling though, pushing/compressing too easily goes off axis.