Wilma kicking our butts in at work!!

[4402tuff4u]

These photos were taken about 1:00 PM and the water was already starting to enter the cofferdam that is supposed to be dry! It's still not high tide. High tide is at 4:00 PM, so this structure will be underwater sometime soon. On normal conditions, you have approx. 5' between high water and the top of the cofferdam. At 1:00 PM (3hrs to high tide to go) the water was already coming in!! The photos do not resemble what is going on onsite. The unleashed force of mother nature is amazing. We will be pumping out all night long so when the tide drops the cofferdam does not rupture under the internal loads applied by the water. We will try to keep the water levels (in & out) even until we gain on it. Then we can dewater it again.  

[Just 6T9 CHGR]

In landlubber terms please.....

[Charger4404spd]

In landlubber terms please.....

Means "Oh shit ......run !"

[4402tuff4u]

Sorry guys! The cofferdam is basically a tub/box that is constructed out of steel and it extends to a depth of about 20' below the water surface. This is built so workers can go inside and build the footings for the new bridge. This tub is built around concrete piles that will support the weight of the bridge. Similar to the footings supporting the Verrazano Bridge here in NY or the Golden Gate on the west coast and all other bridges sitting in water. Anyway this structure called cofferdam is supposed to be dry - no water in it. Due to the high tides brought upon by Wilma, we had to get all the workers/tools/equip out because the tides/water level were coming up pretty quick. Sure enough it came over the top of the tub and flooded it. The next danger is that the outside water level will drop as the tide drops, meanwhile the tub will be full of water. This tub is significantly weak in the other direction of holding the weight of the water in. (64 lbs/cf).

[Charger_Fan]

Man, I'd be afraid of the walls caving in if I were 20 feel below water level in that thing. So what's it rated for holding the water out, somewhere around 1,000 lbs/cf?

[Just 6T9 CHGR]

Now I get ya......I suppose those cylindrical shapes are forms for concrete?

Got any pics of the tub empty?

[Chris G.]

I surprised you guys got so much rain. We barely got anything in NJ. I would have thought the rain 2 weeks ago would have been worse, but it looks like you got hit pretty hard.

Good Luck tonight and stay safe. I hope you get that water pumped out. At least you're making some good O.T. right? That's always nice.

[Tom_440]

Yikes! Stay safe and thanks for the lesson. I recall seeing how they did it in the old days with an upside down "bowl" placed on the ocean floor to keep the workers dry while they dug to the bedrock. Seemed lots of folks got the bends when they came up, and nobody knew why.

[bull]

Wilma isn't so bad. She seems nice to me.

[4402tuff4u]

I surprised you guys got so much rain. We barely got anything in NJ. I would have thought the rain 2 weeks ago would have been worse, but it looks like you got hit pretty hard.

Good Luck tonight and stay safe. I hope you get that water pumped out. At least you're making some good O.T. right? That's always nice.

OT!!! I wish! You know how it goes, "project management" does not get overtime in the private sector. OT would be great. Some of our union dockbuilders are taking home $ 1,900 a week!! At that rate I would of purchased a totally restored Charger. Anyway, these photos show the cofferdam/tub empty while crew work inside last week.

Charger_Fan, with all safety factors calculated in about  5,800 lbs/sf of load.

6T9, after crews place approximately 50 tons of steel reinforcement inside this tub, it gets filled with 1,700 yards of concrete. The bars you see sticking out of the water are the tops of the concrete cylinder piles that are driven into the bay bottom 160' deep. There are 22 of these 160' piles supporting this tub that the bridge will built from.

[Shakey]

Do you have to let the concrete settle for 28 days?  I can't imagine but...

How about the re-bar, what size is it?

Quite amazing on what mankind is capable of doing eh!

Oh yeah, overtime in Project Management - ha!  Are you on call 24?

[PocketThunder]

Do you have to let the concrete settle for 28 days?   I can't imagine but...

How about the re-bar, what size is it?

Quite amazing on what mankind is capable of doing eh!

Oh yeah, overtime in Project Management - ha!   Are you on call 24?

I would guess 28 days goes by before the get around to setting the steel on top of the foundation.  Plus i would think the ocean water surrounding the cofferdam helps to keep the concrete cool while it cures....

[4402tuff4u]

Do you have to let the concrete settle for 28 days?   I can't imagine but...

How about the re-bar, what size is it?

Quite amazing on what mankind is capable of doing eh!

Oh yeah, overtime in Project Management - ha!   Are you on call 24?

I would guess 28 days goes by before the get around to setting the steel on top of the foundation.   Plus i would think the ocean water surrounding the cofferdam helps to keep the concrete cool while it cures....

Rebar in this project ranges from no. 5 (5/8" dia) to the biggest no. 14 (1 3/4" dia), both epoxy coated and black.

The pictures are of the second tub. The first tub was poured in August. Actually we had a network of 2" diameter pipe with pumps to cool off the heat given off by the concrete as it cures. At one end the water was going in at 60 degrees and at the other end it was coming out at 96 degrees. We also introduced liquid nitrogen to the mix as the trucks began to mix it onsite. Normally you use ice, however all the local large ice companies where tied up with New Orleans relief for the mess left by Katrina. It's an early strength 5,000 psi concrete mix. At 7 days we had 3,800 psi. At 12 days we were at 5,700 psi and 6,200 psi at 28 days.

Yep! no OT, on salary only. The NY state Dept of Transp., our client, has all of our personal numbers of our homes. If something looks bad we get the call. So far no calls.

[472 R/T SE]

Righton I miss the field.
I was gonna say you guys prolly use some pretty hot concrete but you beat me to it.   We used to do tilt-ups, concrete slabs on the ground you pick with the crane and set for walls.  I was always on the big iron so it was nothing to pick 75ton panels not counting rigging.
Carpenter's would pour on Friday and we'd be setting on Tuesday, I know they did their tests on blow out for pick points but that always just seemed to soon for me, of course I'm on the ground running the show.   Which way do I run!

[Charger_Fan]

OT would be great. Some of our union dockbuilders are taking home $ 1,900 a week!!

Once again, it's painfully obvious that I'm in the wrong business!

[Lowprofile]

Wilma isn't so bad. She seems nice to me.

Wilma is a milf....well, if I was a cartoon I would do her.   hehehehehe