Lorry crashes into and demolishes pedestrian bridge.

[berkshire]

Apparently the M20 was blocked for 6 hours as a result of this accident.
I thought bridges over freeways were supposed to be designed to withstand this.

B.E.

You are judged not by what you know, but by what you can do.

 

[oldestguy]

Unlikely that a designer can forsee all the stupid things people do when hauling equipment. Fortunately most roadway bridges have enough mass that complete failure does not happen. For example take this OG. I had a bicycle attached to the top of my car and went under a very low rail road bridge well marked to keep trucks out. The bike escaped with maybe with maybe 1 mm of clearance.

 

[itsmoked]

Interesting that the excavator doesn't even look blemished after the event. It makes that bridge look a little tooo weak to me.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[itsmoked]

Maybe not. Seems 60MPH excavators pack some serious kinetic energy.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[itsmoked]

Keith Cress
kcress -

http://www.flaminsystems.com

 

[msquared48]

Enough energy to put the draggin' wagon frame on the ground too...

Mike McCann, PE, SE (WA)

 

[berkshire]

I see , if an excavator can do that to a vehicle bridge, a pedestrian bridge does not stand a chance.
B.E.

You are judged not by what you know, but by what you can do.

 

[oldestguy]

Maybe it takes some sort of extra fee for hauling back-hoes, more or less insurance for fixing their damages caused.

 

[IRstuff]

Maybe, it just takes hiring a hauler that can figure out how tall their load is?

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529

 

[MacGyverS2000]

This pedestrian bridge didn't survive too well...

https://www.youtube.com/watch?v=mk15ovhwrqc

Dan - Owner

http://www.Hi-TecDesigns.com

 

[TenPenny]

Interesting that the article says people were stuck on the highway for 6 hours. Did the concept of backing up to the last exit not occur to anyone?

 

[JohnRBaker]

Have you ever tried to get 3 or 4 lanes of traffic to ALL back-up to the last exit?

Actually Texas is one of the few places where they've addressed this issue directly. Virtually every mile of freeway has what they call 'service roads' on each side of the interstate and there are no fences or barriers along the side of the highway so it's easy to just drive off the shoulder and onto the service road. In fact, my son, who's lived in Texas for something over 16 years, jokes that when you see obvious tracks in the grass down onto the service road, he says they call that a "Texas Off-ramp".

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[cranky108]

John, That is actually logical, which is why we can't do that here. The lack of roads means in some places 30 mile detours. Besides that it would mean the state would have to spend money in places outside the state capital city.

And how about the concept of turning around to go back to the last exit.

But maybe if you are a trucker, and are required to only use the main highways, then there maybe no other option. Pull over and sleep it off.

I'm sure the rules are different there, and someone had a reason for the design they have.

 

[msquared48]

This looks like a new, quicker method to demolish a highway bridge.

Mike McCann, PE, SE (WA)

 

[JStephen]

I remember when I was young, there was a particular underpass up in the Houston area where a highway went under a railroad, with something like a 13' clearance (IE, lower than normal). That underpass was finally taken out by a trackhoe in similar fashion to those above. Get one of those things moving fast, and you've got an unstoppable-force-meets-immovable-object situation.

 

[zeusfaber]

Reversing on the motorway is thoroughly frowned-upon here.

The two junctions nearest to me are ten miles apart - which is well short of the longest stretch in the UK, but still a long way to be be going "wrong way" down a major road without being really sure that you aren't going to encounter someone coming the other way at 80+ mph.

Then there's the difficulty of getting articulated vehicles off the motorway at the junction (the entry angles aren't nice and the roundabout needs to keep running the right way to cater for traffic arriving from the other direction).

With all that in mind, current strategies seek to minimise closure duration first, provide in-situ welfare for stranded travellers if that isn't possible and evacuate them from their vehicles as a last resort.

A.

 

[JohnRBaker]

I know that this is a bit off-topic, however, since we've been looking at a lot of pictures of excavators and other large yellow pieces of equipment, and I further suspect that many of us, when we were kids, may have had 'sand box' toys modeled after stuff like this. And so I thought it might be of interest to learn that there's a place outside of Las Vegas, NV where you can go and 'play' with the real thing:

http://digthisvegas.com/

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[LittleInch]

There is something odd about this.

The lorry with the low loader was apparently going slowly along the hard shoulder.

It has clearly passed under the gantry sign just before it.

The footbridge is a curious design with a narrowing section to allow a slope on the bridge while keeping the bottom flat and set height above the carriageway.

It would seem that the bridge section just rested on the pillar and on the midway joint.

In terms of backing up that is what happens normally. However, the location here was odd. The London bound carriageway was not far from a junction and was cleared. The southbound carriageway - the one with the bridge still standing is just beyond a complex motorway junction which made it very difficult to reverse traffic.

In the end they decided that the bridge left standing was secure and allowed traffic under it.

Motorway was closed for a day and a half.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[IRstuff]

The gantry sign appears to have about 2 ft higher clearance than the walkway

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529

 

[LittleInch]

Difficult to judge from any photo I've seen and especially when you look at vertical distance above the edge of the hard shoulder, not the extreme end.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.