Engineering Question

[beermonkey9417]

not an engineer... but as a Mechanical Technologist, I am qualified in many of the fundamentals of the engineering.

... there are many ways to aproach the above problem, intelligently exploring the dynamics involved in the above structural and mechanical failure...

however, I fear there was very little intelligence involved in the accident.

i concure...

 

[87canadiancutlass]

Yes I agree with the can opener. But I would also like a side of momentum. Take a block of steel moving at 70mph or 110kph and it takes a lot of energy to stop that. Not to mention its able to keep momentum while the boom moves backward.

 

[khan0165]

I should mention, concrete has almost unmatched strength in compression. However, can handle very little stress past it's yield under tension or impact loading, especially under point loads.

adding the dynamic force @ 60mph (some kinetic energy there) of the digger's arm, with a small cross sectional area (relative to the side of the bridge)... On a larger scale, it does produce somewhat of a "knifing" effect...

Although, I think we can consider Beer's theory on this as well...
(great diagram by the way, my college Dynamics proff would be proud)

 

[oldsofb]

92.6 mph by my math.

 

[tc1959]

 

[pontiacgp]

I posted it just for fun and never expected anyone to try analyse it but one conclusion I think we can all agree on is Beer is overqualified for his job...

 

[bill]

This kinda thing isnt good for our nations infrastructure....lol

 

[am4blue]

I bet the whole front end (left side) of that digger lifted up and slammed back down.
The weight distribution on those things, I believe, requires a counterweight opposite the direction of dig. It would be on the right had side, opposite the way it digs. I bet the arm hit on the right side of the bridge then the whole machine tilted on it's tracks to the clockwise until the bucket smacked the overpass on the left.

See where, looking from left to right on the bottom side of the overpass, there is a pocket that is broken out? Then moving to the right, there is a section that appears to be untouched. I bet the bucket hit where that pocket was created causing the whole machine to tip clockwise.

With the bucket hitting the left side of the bridge and the whole machine tilting to the right, the arm of the digger would have drug along the right side until it had enough force (and the arm passed the main support of the bridge) to break up through the road.

 

[beermonkey9417]

I posted it just for fun and never expected anyone to try analyse it but one conclusion I think we can all agree on is Beer is overqualified for his job...

i concure...