100m at 1 lane is around 430SY. That's probably 2hrs of milling and an hour of tacking and paving, with maybe another hour or so for incidentals. So you may only get half a workday of production. For time consuming repairs, like full-depth replacement, the setup time cost may not be significant.

Keep in mind, though, you don't lose a lane of traffic. There is no need to truck in jersey barriers. You don't have to build an entire temporary detour road. You don't pay a consultant $200/hr to design a traffic control plan.

I think the real value is safety. The crew is shielded by the bridge and you have complete grade separation from traffic. That's a lot better than an orange barrel being the only thing between you and a minivan.

430SY? What's SY? Square yards?

Yes. We don't use metric in the USA and you can't make us :)

I'm not American, but I would have understood what you meant had you written sq yd instead.

I have a addon that autoconverts imperial units. Your comment is the only thing peaking out of the insanity bubble. =)

>Yes. We don't use metric in the USA and you can't make us :)

NASA demonstrates otherwise.

And the military, and for science, some parts of government. And wine bottles and soft drinks, but not milk or beer.

It’s like Windows with its half-hearted efforts to modernise it’s interface.

> no need to truck in jersey barriers.

The video clearly shows barriers between the workers and the active surface lane.

Once installed, the bridge can be driven along the road when a 100m segment is finished

oh this is cool. I did think for a 2 day setup and 1/2 day takedown it wasn't a huge efficiency saving but it is if you move it down the road at the same time. As the comment above mentions, safety is a huge factor too.

Presumably the road has to be closed for the bridge to travel? I assume this takes place at night.

During the night, there will be 1 lane open in each direction (one on the side of the bridge, and one on the opposite carriageway), so the bridge can be moved.

If it's moved slowly enough, I don't see why traffic couldn't drive on it.

I guess it's theoretically possible to engineer a bridge that can move with traffic on it.

But this bridge is engineered with solid feet for taking traffic loads. The wheels are only extended for movement and wouldn't be able to take the load of traffic.

That probably just takes a few hours, easy to do. And you can start/stop a few times to let cars go over.

I think they pave 100 m, wait til it's dried (next day, perhaps) then drive the bridge 100 m up the newly paved bit and start again. No break

No. This bridge travels. Look closely: it has wheels and it's motorized.

> That seems horribly slow and expensive.

That’s because it is. Welcome to the world (in the case of USA, the entire country) car centric transportation.