Watch a highway bridge be replaced in under three days, live | Hacker News Reader

Watch a highway bridge be replaced in under three days, live

verandaplan.org

54 pointsgumby32 comments

This is literally within walking distance of me and I have a friend who is working on this project.

Sure the actual replacement only takes 3 days, but it's been worked towards with construction on the area and the roads underneath for something like a year. It's a very affluent area, and an absolutely vital corridor into and out of the city for employees, because affording living close to the city is laughably difficult.

The common joke here in Maine is that there are two seasons: Winter, and construction.

What was wrong with the old bridge? Not that I know anything about bridges but it looks newish.

Look at the abutments on the west camera - the new bridge is obviously wider.

I suspect they're adding a lane in each direction.

Ah I was wrong (or not completely right, the new bridge is wider but adds shoulders):

> Problem: The Veranda Street Bridge carries Interstate 295 (I‑295) over Veranda Street (U.S. Route 1) in Portland, Maine. The existing bridge was built in 1961 and, after 60 years of heavy use, its condition has deteriorated. A 2017 inspection of the bridge determined it’s in satisfactory to poor condition and is structurally deficient.

https://verandaplan.org/project

Same problem with nearly every bridge in the US: It's really old and past its design life and should have been replaced ten years ago.

that's a huge exaggeration. We have problems but to declare every bridge bad is hyperbolic.

That is a very common joke in Wisconsin as well, which leads me to believe anywhere north of the 37th parallel has the same joke.

It feels like this should be titled something more to the effect of, "watch a bridge section be constructed on site and then installed over the span of a year." Noting it as "replaced in three days" feels wildly inaccurate.

Time on site seems like a massively critical time variable, especially with infrastructure people want to use, e.g. a road/highway. Time off site is presumably much cheaper, certainly less disruptive.

The title feels informative to me.

I'm not sure what you mean about time on site, could you explain? They've been building this section of bridge "on site" by my understanding of the phrase, and have had the road way under the bridge diverted by construction for the past year. It appears to have been permanently redirected now. I assume during some of the work to the existing bridge, they've had traffic slowed, diverted, barreled, etc. Actual moving of old section out and new section into place in three days seems to pretend this was a speedy project with only minor disruption to local traffic, which doesn't seem quite right to me. I guess if the thought is just that that highway connected to the bridge is only (fully) closed for three days, that's certainly worth something over having it closed for the year it took to do the project.

According to the FAQ https://verandaplan.org/faq the road under the bridge is closed for 7 days (already closed) and the highway is closed for 3.

All in all that's a pretty low amount of time; often these are done by closing the road under for an unspecified amount of time, diverting all traffic onto one bridge span (reduce to one lane in each direction) and replacing the bridge a half at a time.

I misunderstood; you’re right, but as sibling comment says, short time to close down the affected roads completely matters.

So Usain Bolt can win gold medal in Olympics under 10 seconds totally disregarding all training he spent time on.

So all that matters is people watching it on TV?

I disagree much, because building site was there for months and road below was hindered all the time. Highway was maybe operating without closing lanes but that is not the full story there.

Your example would seem to answer itself. No-one understands the 100m record to be 17 years.

You and the sibling commenter are definitely correct, this construction method definitely appears to be preferable to just killing the road for a year. My qualm specifically is that the title doesn't really tell the full story (clickbait). I, at least, clicked it because I wondered how they could possibly have done all the prep and work in that sort of a window and the answer was they couldn't, but they still got my click.

Here is a similar project with a time lapse video in Ottawa, Canada

https://www.youtube.com/watch?v=zDcMMPuk3Dw

Pretty ingenious to shove dirt under the old bridge to make demolition easier.

The "build it nearby and move it into position" has become all the rage lately, it's been proven multiple times and has advantages, even with longer spans like the St Croix Crossing.

Another one in China: https://www.youtube.com/watch?v=cKi8VWRDA_c

Very impressive. Those stretches of prefabricated girders are sometimes hundreds of miles long because they built them to preserve land usage underneath even in areas the Terrain would allow surface-level tracks.

As a Masshole I cringe at all the opportunities for make-work handouts and "not quite graft" this kind of efficiency forgoes. Those backwards hicks up there would be so much better off if they did things our way. We really know how to run a state. They need to think bigger. That simple bridge replacement, it should take a year. It should tie up hundreds and hundreds of orange barrels. There will need to be rental equipment parked on site for at least six months. If the local communities are rich, you gotta make sure they tie you up in court over the minutia so you can spend thousands on politically connected law firms. Triple the timeline if you're within 5mi of a wetland. Etc. etc.

(sarcasm should be obvious)

I lived on Oahu for several years and am still blown away by the time and cost expenditures for the monorail system that will (in 2031) connect the west side of the island with the mall in Honolulu. Construction started in 2011 and the first phase, which only goes about half of the total distance, won't open until late this year!

Huh what even is that thing? Have they never heard of regular light rail?

14 bridges were replaced on I93, each within 55 hours, in 2011.

http://archive.boston.com/news/local/massachusetts/articles/...

It's incredible the money and logistical thinking devoted to highway construction and maintenance compared to almost any other kind of infrastructure in America. Like, imagine they decided trains were as high a priority.

They did, it's just privately owned, maintained, and operated by freight companies. [1]

[1] https://www.researchgate.net/figure/The-North-American-Rail-...

The rail networks in the US are actually dwindling [1], from a peak of ~250,000 route miles in the 1920s to less than 100,000 today. The USDOT maintains over 4 million miles of highway.

[1] https://www.railserve.com/stats_records/railroad_route_miles...

Most of that is because of trucks for last mile. Whereas trains used to go right into factories they don’t even slow down in the same towns now.

Salt Lake just did this for one of the bridges across I-80. Amazingly the actual swap took less than 24 hours.

Riveting

Was expecting a time lapse. Not a live view.

There is a time lapse, but it's a link on the landing page.

Welded to my seat.

just beam-ing with excitement

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