There just aren't very many things in this world that will get me up out of bed at 05:30 AM.
Deer hunting qualifies. So does leaving for a vacation or motorcycle trip.

My Girlfriend works in the heavy road/bridge construction field as an Engineer. (she is also a SIG Forum Member)
G/F is doing a multi year project over in the next county, replacing an old two lane road bridge over a river. 50+ years of road salt has "killed" the old bridge.
The old bridge is about ready to collapse, and they will tear down the old bridge, and build a new one.
The problem geographically, it's a 23 mile detour to the next nearest bridge over the river.
The local Fire/EMS people raised a big enough stink, the big bosses decided to install a temporary bridge right next to the old bridge for usage while demolition/removal/new construction takes place.
My Girlfriend asked me to show up with my drone and take some photos & video of the temporary bridge installation.

ACROW is a "brand" of temporary bridge, based in Parsippany, New Jersey. These temporary bridges are composed of "sections" bolted together.
This ACROW temporary bridge is a single lane bridge, with traffic lights to control traffic flow in both directions.
The bridge is cantilevered over the river with a good sized John Deere bulldozer chained to the end of the temporary bridge as a counterweight, and then the bridge is "shoved" by the bulldozer while a big hydraulic crane lifts the unsupported end.

They had it most of the way across the river very early this morning, and got "alarms" on the crane. Rather than drop it into the river, they pulled it back where they started from.
After adding additional crane counterweights and supplemental pulleys/cables for the crane, they started the procedure a second time.

The temporary bridge "skeleton" was successfully installed, and the roadbed on the temporary bridge, along with the entrance/exit roads for the temporary bridge, and traffic lights will be done soon.
Once the temporary bridge is finished, the old bridge will be demolished and removed. Then construction on the new replacement bridge begins.

The representative from ACROW was there this morning. I asked if the temporary bridge was rated for a 80,000 pound tractor trailer rig. The answer was "YES" and a handful of automobiles/trucks in addition.
I was flying a DJI Mini 2 drone. Maximum altitude was 392 feet above ground level.

DJI_0087 by cee_Kamp 32ACP, on Flickr

DJI_0162 by cee_Kamp 32ACP, on Flickr

DJI_0169 by cee_Kamp 32ACP, on Flickr

DJI_0197 by cee_Kamp 32ACP, on Flickr

DJI_0179 by cee_Kamp 32ACP, on Flickr

DJI_0192 by cee_Kamp 32ACP, on Flickr

Nice shots, the ACROW company might want to see copies of them.

Cool pictures. Thanks for sharing.

Very cool, the drone captured the event in a way no words could describe.

That is amazing. Thank you for sharing the pictures.

An amazing bit of engineering! Thanks for sharing the pictures. It appears that the actual placement of the temp. bridge skeleton was done in a half day or less.



edited to add a missed word.

I would have thought something pontoon-based would be easier.

Just create a low-water crossing or ford in that little river. Problem solved!

That's cool! Thanks for sharing the photos.

It took the bridge assembly crew multiple days for assembling
all the sections together. They are bolted together.
650 foot/pounds bolt torque if I recall correctly.

Yes, less than a half day for getting it across the river.
Even counting two attempts.

I did ask the ACROW representative for a business card.
I emailed four photos to him earlier today.

In addition, I took a high resolution video of the last 25 feet
for the bridge reaching the crane side abutment.
But with a file size of over 800 MB, it isn't easily transferred.
2.5 minutes of video, approaching 1 GB file size.

Using the drone is the only way to keep the skills sharp.

That's very cool. At one point in my life I wanted to be a civil engineer. It never panned out, and probably for the best, but I still find that kind of stuff fascinating. Thanks for sharing the pics and a description of the process!

I was a clerk-typist in the Army, but I remember the engineers put up Bailey Bridges:

https://theprinciplesofwar.com...g/the-bailey-bridge/

I was 12B in the National Guard, MI. We did the ‘Bailey Bridge’. I know we put up a complete one at Ft Leonard Wood, MO. Not sure if we did a complete one in Michigan, maybe Camp Grayling.

#1 The easy way.



#2 The hardest way.

It's a beautiful mother bridge.

Great post - cool stuff! I love reading about engineering feats.

No middle supports, entire span of temp. bridge is supported at each end only, correct?

Very cool. What part of NY?

I think Civil Engineering and all varieties of Physics are the most interesting things. But I would think Civil projects are the most interesting if push comes to shove. Because you can put your hands on it and see it grow on site first hand.

By looking at it I would hazard to guess that structure is loaded to the hilt with two-force members, esp considering its portable modular nature.

^^^
Yes, the temporary bridge is supported at only the ends.
There is no center pier.

Location is South New Berlin, NY.
Rt. 23 crossing the Unadilla River.

Very cool. I used to visit Guilford years ago. That would’ve been some detour without that bridge.