Bridge Collapse Dresden (11/09)

[duesselmartin]

For those visiting Dresden or those interested in its transport system.
A bridge carrying tram Tracks collapsed last night in Dresden.
Tram, road and shipping is closed and diverted.
Cause is yet unknown.

Germany: Bridge in Dresden collapses into Elbe river – DW – 09/11/2024

Police officers nearby described loud noises and the the ground shaking at part of the Carola Bridge fell into the river. No cause for the collapse has been determined as of yet.

www.dw.com

A 100-meter (330-foot) piece of the Carola Bridge in the inner city of Dresden collapsed early in the morning on Wednesday, local authorities reported. The bridge is one of four crossing the Elbe river in downtown Dresden and the incident is likely to cause major traffic chaos in the eastern German city.

City officials said that due to the early hour, no one had been on the bridge and thus no one was hurt in the collapse, but that both car and ship traffic on the key waterway would have to be stopped for an undetermined amount of time.

 

[YorkshireBear]

Quite concerning it would collapse just like that. I'm trying to find out what type of concrete construction it is with limited success at the moment.

 

[stuu]

Quite concerning it would collapse just like that. I'm trying to find out what type of concrete construction it is with limited success at the moment.

Pre-stressed concrete beams, according to German Wikipedia

Carolabrücke (Dresden) – Wikipedia

de.wikipedia.org

 

[YorkshireBear]

Pre-stressed concrete beams, according to German Wikipedia

Carolabrücke (Dresden) – Wikipedia

de.wikipedia.org

Thanks, no idea why that didn't show up in my searches.

Not surprised it's prestressed concrete, I hate the stuff.

 

[nwales58]

Although it was built by the DDR it is the same age as the many bridges, particularly motorway, in the former BRD that have been causing so much disruption. Imagine the district heating mains emptying the whole system into the river.

According to the Wikipedia article the 2019 renovation found the structure to be OK.

I'm not a civil engineer - what is carbon concrete (Carbonbeton)? Used for the widened walkways in 2019.

 

[stuu]

I'm not a civil engineer - what is carbon concrete (Carbonbeton)? Used for the widened walkways in 2019.

Using carbon fibre instead of steel for the rebar

 

[DanielB]

According to the Wikipedia article the 2019 renovation found the structure to be OK.

According to German media, the collapsed section was due to be refurbished in 2025. It will need a bit more refurbishment now...
The last tram apparently passed over the bridge just 18 minutes before it collapsed!

 

[Beebman]

Here's a 2-minute video (without commentary) posted about 30 minutes ago by a local media production company which has some good close-up views of the collapsed bridge:

The tram rails appear to have been torn from their fastenings and are suspended in mid-air.

 

[LNW-GW Joint]

It appears the already-upgraded eastern and central sections of the bridge, carrying road traffic, did not collapse like the western section (which carries tram tracks and footpaths).
But the whole bridge is closed until further notice.
The current Google Maps view shows the central section of the Carolabrücke in the process of being upgraded.
The rail bridge over the Elbe at Dresden is 1.5km or so to the west.

 

[stuartmoss]

Quite concerning it would collapse just like that. I'm trying to find out what type of concrete construction it is with limited success at the moment.

The bridge was widened using a new type of carbon-concrete only a few years ago…I’m there right now and have been given the info by the locals, I’ll post some pics in a separate reply shortly.

On a separate note, there has also been a tram derailment elsewhere!

== Doublepost prevention - post automatically merged: 11 Sep 2024 ==

Here are some pics of the Carola Bridge and another of the tram derailment, which was on Große Meißener Straße. I will get some more pics tomorrow, it started raining and I’d already done 24k steps, so was ready for home.

 

[DelW]

Pre-stressed concrete beams, according to German Wikipedia

Carolabrücke (Dresden) – Wikipedia

de.wikipedia.org

From the pictures and the Wikipedia page, I think that rather than pre-stressed beams, which would have been cast and stressed in a factory, the bridge has (three) separate box girders, cast in situ, with pre-stressing cables located in ducts in the webs and stressed on site. This was a common design in the 1970s, and required the cables and ducts to be fully grouted up to protect the cables from corrosion. However, because of the up and down profile of the cables, it was difficult to ensure that the grout had fully penetrated and that no voids were left. (I worked on construction of such a bridge in 1973-4, which fortunately still seems to be safe).

In recent years a number of such bridges have suffered cable corrosion, including notably Hammersmith Flyover which needed emergency repairs just before the 2012 Olympics. There, additional tendons were fixed to the sides of the girders, an ugly but effective solution.

As soon as I saw the Dresden photos on the web, my first reaction was that it looked typical of a pre-stressing failure, so it will be interesting to see whether the investigation confirms that or not. I imagine that will be undertaken rapidly, as there will be an urgent need to get the wreckage cleared from the navigation channel, and a new bridge built to restore the tram connections to Neustadt.

 

[stuartmoss]

My colleague in Dresden has told me that trams won’t be running over that bridge for 5 years. He said it was on the news. All of the trams seem to be diverted over the Augustus bridge today, there’s one passing every 30 seconds right now.

 

[Dunfanaghy Rd]

Blocking the Elbe to barge traffic is going to hurt.
Pat

 

[jon0844]

Imagine the district heating mains emptying the whole system into the river.

Will make the river nice and toasty for swimmers then...

(I am aware that until last week, Germany was going through somewhat of a heatwave anyway!)

 

[The exile]

Blocking the Elbe to barge traffic is going to hurt.
Pat

Going to be a quiet time in the Czech free harbour in Hamburg!

 

[Beebman]

Video of overnight demolition work (German commentary):

Imagine the district heating mains emptying the whole system into the river.

At 0:55 in the video a large cloud of steam can be seen rising after one of the controlled explosions and if my understanding of the commentary is correct it's coming from a broken heating main.

Blocking the Elbe to barge traffic is going to hurt.
Pat

I understand that the local Weiße Flotte passenger boat service is running in two halves either side of the bridge with a bus shuttle inbetween.

== Doublepost prevention - post automatically merged: 13 Sep 2024 ==

Regional TV station MDR has set up a webcam showing work currently taking place on the bridge: