Construction vs. Deconstruction

[knight1fox3]

As much as I enjoy seeing new structures being constructed, I'm equally fascinated by those that also need to be deconstructed.  The photo below is the deconstruction project for one of our older company parking ramps.  I'm curious as to how a particular contractor would even begin to approach this project. Since it's unlikely to be the same contractor who built the ramp, they would obviously need all the building/structure plans. WI is not a seismically active area, so would they need to perform any ANSYS modeling to determine critical load-bearing points? Or would that be easily ascertained by someone who is structurally qualified to review the drawing package for the ramp? I believe they started by removing the top concrete layer, then proceeded to remove the column portions for that same particular level only. Then I would imagine they would just repeat that process for each of the subsequent lower levels of the ramp. Anyway, I just found this to be interesting. Would be curious to hear from @MA_PE, @Ble_PE, and anyone else that may know more about this than I do. :thumbs:

View attachment 8446

 

[jeb6294]

Pansies....blow that $hit up!

 

[csb]

You just reverse the order of the plans. 

 

[Supe]

 

[knight1fox3]

Pansies....blow that $hit up!

You just reverse the order of the plans. 

ldman:   Though I should have half-expected some smart-@ss responses.  Well played.

 

[Flyer_PE]

I've been watching a power plant demo project for a while.  Definitely a different mindset to demolish than it is to construct.  The companies doing the work here specialize in demolishion only.  As one of their site managers told our engineering manager "We don't build shit, we just knock it down."

 

[MA_PE]

you definitely need  a plan.  Big diamond saws are your friend as you can cut large portions, bring them to the ground and then crush/smash/chop up into smaller components.  Implosion is always an option.  Methods depend on what needs to be saved, how much staging room there is, and impact to surrounding buildings and occupants.  Problems can arise if the smaller demolition activities proceed without controls as the equipment works above.  It's always a risk that they start weakening the strutcure below without proper consideration of the construction loads working above.  The sometimes tricky part is that when evalutaing temporary construction loads engineers often use lower load factors than are used for design, so the potential so the demand:capacity ratio gets closer to 1, and it's important to consider the "dynamic" effects of equipment movement and impacts and not just the static loads/weights of things.

 

[Road Guy]

 

[Flyer_PE]

The wall was there before lunch.  Dropped the whole thing in one piece:

 

[snickerd3]

^that had to have been one big ass sawzall

 

[Flyer_PE]

^that had to have been one big ass sawzall

They cut the siding on both sides and let the wall fall away like a draw bridge.  One of my buddies shot video of it and I'll post a link to it when I can. 

 

[knight1fox3]

The wall was there before lunch.  Dropped the whole thing in one piece:

Ooh!  I spy a couple of double-girder bridge cranes!  Any way to get a shot of the main crane nameplate?

 

[Flyer_PE]

Ooh!  I spy a couple of double-girder bridge cranes!  Any way to get a shot of the main crane nameplate?

I may be able to score something.  I'll be back on site Tuesday or Wednesday of next week and will see if my picture taking friend has.  They're planning to drop the the cranes to the turbine deck next week to start cutting them up.  I'm betting either he or I can just walk up and take a few picutures after they're on the deck.

 

[knight1fox3]

They're planning to drop the the cranes to the turbine deck next week to start cutting them up.  I'm betting either he or I can just walk up and take a few picutures after they're on the deck.

That is somewhat surprising. Though I do not know what their operating condition is and/or if they have any level of contamination. Seems like they would be able to sell those off rather than scrap them. But probably more trouble than it's worth.

 

[Flyer_PE]

I've been amazed all along at the things that have been scrapped rather than sold off as useable equipment.

 

[snickerd3]

I've been amazed all along at the things that have been scrapped rather than sold off as useable equipment.

stigma of being used at a nuclear facility?   who would want something that was used at a nuclear facility, just being there it is contaminated mindset.

 

[Flyer_PE]

stigma of being used at a nuclear facility?   who would want something that was used at a nuclear facility, just being there it is contaminated mindset.

Their asset recovery program was/is pretty much non-existent.  There was a lot of equipment that I figured would be of use to other nuclear plants but they only had one person doing asset recovery and it wasn't even his primary job. 

 

[knight1fox3]

Who would want something that was used at a nuclear facility, just being there it is contaminated mindset.

Mostly just other nuclear plants (business-alliance partners).  Since they are well-versed in being able to deal with any sort of con/decon. :thumbs:

 

[Flyer_PE]

A few demo videos:

South Turbine Building Wall:

South Wall

Unit 1 Turbine Building Crane:

U1 TB Crane

Unit 2 Turbine Building Crane:

U2 TB Crane