The bridge.

[Absledder]

kind of. if you connected all 3 girders east, west,centre and lifted it onto the abutments it could support its own weight. but seconds later the centre section would flop sideways just like in the photos just due to the sheer weight of the girder. like i mentioned earlier these things are incredibly flimsy in torsion by design for weight savings once all girders are cross braced together they become one solid unit which is now torsionally stable. I am not a structural engineer just speaking from my bridge building days as a project manager.

Lol after reading your first post I was wondering how a surveyor knew so much about bridges. So far your answer seems the most likely but I guess we won't know for a while. How long do you figure it would take to make new girders if they need to be replaced?


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[imdoo'n]

Polaris engineers? or BRP?

 

[maxwell]

Lol after reading your first post I was wondering how a surveyor knew so much about bridges. So far your answer seems the most likely but I guess we won't know for a while. How long do you figure it would take to make new girders if they need to be replaced?


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that's the SCARY part. i know when we tendered our girders it was a year long process from fabrication to installation. seeing as supreme steel already has everything approved and signed off from the engineer i would assume they could cut that time in half. but you can bet they wont be re fabricating anything until they investigate and prove it wasnt a design flaw. otherwise the city of edmonton has some huge problems.

 

[T-team]

Let's hear from all you armchair engineers. What the fawk happened?

Judging by the angle of the bend on the vertex of the third pillar, I belive that the engineers forgot to take into account the wind velocity coming over the apex the the hill beind the pillars at a 43.5 degree angle.. which in turn had caused a little bit of soil erosion thereby causing the ends of one of the pillars to sink into the ground adding an extra 5 newtons of force on the front of the beam.... and follwing the formula...( 5x19-8(5x2)-=5>12.45689+1-.0009-15+9-1+8X3.14+13-1 ) the stress on the inside of the pillar became to great thereby causing said pillar to implode causing such force it actually put a negative pull on the ground surrounding the bridge..... said formula (1=3+4-1+5.5-2X18=1+45) making the other said pillars in question buckle.

 

[Trashy]

Polaris engineers? or BRP?

BRP.... those beams don't like the cold, in 2015 either

 

[catinthehat]

I beams aren't meant for lateral forces. But what could push on the side of the beam to bend it like that? They said it bent before their eyes.
.

Obviously they built it to close to a negative magnetic field thus causing the metal to bend away from the field.

 

[maxwell]

judging by the angle of the bend on the vertex of the third pillar, i belive that the engineers forgot to take into account the wind velocity coming over the apex the the hill beind the pillars at a 43.5 degree angle.. Which in turn had caused a little bit of soil erosion thereby causing the ends of one of the pillars to sink into the ground adding an extra 5 newtons of force on the front of the beam.... And follwing to following formula...( 5x19-8(5x2)-=5>12.45689+1-.0009-15+9-1+8x3.14+13-1 ) the stress on the inside of the pillar became to great thereby causing said pillar to implode causing such force it actually put a negative pull on the ground surrounding the bridge..... Said formula (1=3+4-1+5.5-2x18=1+45) making the other pillars buckle.

omg hes right

 

[Summitric]

brp.... Those beams don't like the cold, in 2015 either

sorry trashy, beams are glued together, so must be polaris engineered.... Hehehehe

 

[Mike270412]

Judging by the angle of the bend on the vertex of the third pillar, I belive that the engineers forgot to take into account the wind velocity coming over the apex the the hill beind the pillars at a 43.5 degree angle.. which in turn had caused a little bit of soil erosion thereby causing the ends of one of the pillars to sink into the ground adding an extra 5 newtons of force on the front of the beam.... and follwing the formula...( 5x19-8(5x2)-=5>12.45689+1-.0009-15+9-1+8X3.14+13-1 ) the stress on the inside of the pillar became to great thereby causing said pillar to implode causing such force it actually put a negative pull on the ground surrounding the bridge..... said formula (1=3+4-1+5.5-2X18=1+45) making the other said pillars in question buckle.

That's the most plausible explanation so far.

 

[Summitric]

So they had 7 installed and putting the 8th one in and the last 4 bent and the first 3 were okay.... At 2:00am they were fine... At 2:15 4 bent.... Ouch. Says they can build 4 new beams but will take almost a year to build. Someone needs fired over this one.

Canada needs to look at replacing bridge sections complete, like they have done in areas of the u.s....huge cranes to remove the old section and lift new sections in. Saw this happen over an evening just outside salt lake city.... Done by morning rush hour, was very kool to observe

 

[Bogger]

It's obviously the DC & Marvel comic groups fawking with us......

 

[TylerG]

So they had 7 installed and putting the 8th one in and the last 4 bent and the first 3 were okay.... At 2:00am they were fine... At 2:15 4 bent.... Ouch. Says they can build 4 new beams but will take almost a year to build. Someone needs fired over this one.

Canada needs to look at replacing bridge sections complete, like they have done in areas of the u.s....huge cranes to remove the old section and lift new sections in. Saw this happen over an evening just outside salt lake city.... Done by morning rush hour, was very kool to observe

may not be feasible in our climate, the melt/freeze cycles etc.

 

[imdoo'n]

someone building a quad bridge by mistake?

 

[Bogger]

There is no water under this bridge it does not concern you.....

someone building a quad bridge by mistake?

 

[tiger666]

That sounds like a very educated opinion.It just looks to me like the crane should be supporting the girder untill all the cross bracing is installed.Just my opinion

how so?

Girder installations are serious business and supreme is the best at it. ( girder supply and erection is typically a one contract item). from the limited details i have and a few photos my conclusion is as follows. This bridge is a single span bridge with 3 girder sections. east west and centre. This means there are no piers for the girders to cantilever and the east and west sections must be temporarily supported past the centre of gravity and chained down at the abutment ends. followed by complete cross brace installation on those completed sections before the centre girders are installed and cross braced. the girders that twisted are in the center section. Steel girders are extremely flimsy in torsion and are designed for only downward force. only when the entire girder structure is cross braced and the concrete deck is cast onto the girders does it become full strength in torsion (earthquake), side load (wind) and down force (vehcles). as girders are installed a team follows quickly behind and installs cross bracing but does not torque all bolts until complete. my "guess" is that the weight of the centre girder sections installed combined with warmer temperatures caused the temporary shoring to sink. This could even be by as little as 20mm to cause this. from the photos you can see the cross bracing team was not able to completely cross brace the damaged section before this occurred. if the shoring did in fact sink this would put extreme amounts of compression on top of the girder and tension on the bottom of the girder causing it to buckle. had they been able to fully cross brace the centre in time this likely would not have happened but it still could have due to the amount of force. In my opinion this is not a matter of poor quality steel ( this is checked and double checked before fabrication and shipping). it is also in my opinion not a fault of the installation crew but more an oversight into the temporary shoring systems in place. i would like to think i am wrong and it was something else because typically all things are considered such as temperature while the contractor and engineer are developing and approving a girder erection plan. I also have a hard time thinking this is a design flaw in the girders for 2 reasons. #1 the girders sitting with no concrete deck or traffic have less than 20% of their design load on them and i dont think they could have fawked that up that bad. #2 the computer software used to design girders is mind blowing. they run them through dynamic and static load tests, wind, earthquake etcetc tests before they are fabricated.

Just my 2c

 

[maxwell]

That sounds like a very educated opinion.It just looks to me like the crane should be supporting the girder untill all the cross bracing is installed.Just my opinion

i would agree. however thats not how it happens but could likely be a contributing factor here.

typically 1 or 2 cranes swing the girders then swing the cross bracing once the girder is bolted in with a few bolts. looks like there was 3 cranes so who knows what was going on there.

 

[Bogger]

Brother in-law is a tower/mobile crane operator...... Him and all his crane cronies will have this mystery solved by happy hour.... Keeping tabs on FB

 

[TylerG]

Brother in-law is a tower/mobile crane operator...... Him and all his crane cronies will have this mystery solved by happy hour.... Keeping tabs on FB

or they'll be plastered and just figure they have it solved.

 

[Summitric]

EDMONTON — Drivers who normally use Groat Road will have to detour for another three weeks after four girders buckled during the 102 Avenue bridge construction on Monday.
Story continues below


[h=3]Related[/h]

• [h=3] Twisted metal over Groat Road leads to indefinite closure [/h]
• [h=3] Get ready for closures of Groat Road and 102 Avenue Bridge [/h]
• [h=3] Groat bridge reconstruction to impact traffic, businesses [/h]
• [h=3] Costs soar for new bridge over Groat Road [/h]

On Tuesday, the City of Edmonton said in order to stabilize the girders, a much larger crane was brought in from outside Edmonton and was being assembled. The weight of the girders will be transferred to the crane so that workers can inspect the steel beams, and begin repairing or removing them.
“Public and worker safety remain our top priority,” said Barry Belcourt, Branch Manager of Roads Design and Construction.“Once the girders are safe and stable, we can begin repairing or removing the damaged pieces,” he added. “As soon as the bridge is re-stabilized, we will remove the crane and re-open Groat Road.”


The road was closed last weekend between 107 Avenue and River Valley Road because the steel girders for the new bridge being built over Groat were being lifted into place.
On Sunday, the city extended the closure to Tuesday morning due to troubles with the girder placement and because of the weather. Around 2:15 a.m. Monday, four of the 40-tonne girders buckled as much as a metre and a half while one of them was being installed.
Work was halted and several engineers were brought in to investigate. The city wasn’t able to identify a single factor that caused the girders to fail, and said it was looking into a number of potential causes, including wind, temperatures, the quality of steel and the way it was being installed.
READ MORE: Twisted metal over Groat Road leads to indefinite closure
On Monday Belcourt said the delay is likely to add to the project’s cost, which is pegged at $32 million.
However, he explained there are penalties in the contract that address the number of days Groat Road is closed.
“Any time Groat Road has four lanes closed, as we’re speaking now, there’s a $15,000 a day rental fee that’s being paid to us, so we have multiple bonuses within the contract to make sure that everybody is not just stepping back and wait and see.”
In the worst-case scenario, it could also push back the bridge’s opening by a year.

 

[Trashy]

sorry trashy, beams are glued together, so must be polaris engineered.... Hehehehe

This is sooooooo 2013 Ric But a good try.....