Footers

When building a rollercoaster over water how do they get the footers into the water?

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Zero-Gravity

Glad you asked that, I've always wanted to know that. Do they have a way to separate the water somehow? And how deep into the ground do the footers usually go?

Sorry I couldn't provide an answer but it drudged up a couple of questions.

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...Agghh, gimme a break will ya?

Most of the time in a park that has a ride over a pond or lake, the water can just be drained and the footers poured like normal. Most of the "natural" waterways you see in parks are actually man-made and have circulations systems. Some good examples are CP's mid-park stream, PKD's Lake Charles, and even Disney World's 7 Seas Lagoon.

However in cases like Indiana Beach where footers lie in a large public waterway that cannot be drained, I am sure the footers are treated just like those for a bridge. They probably use a pile driver to pound them into the bedrock below.

Shaggy

or maybe they pour them some where else them drop them under the water... :)

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Zero-Gravity

Concrete can be poured underwater.

As for Indiana Beach, isn't Lake Shafer's water level lowered every few year for inspections on the dam? I remember seeing a picture somewhere of Hoosier Hurricane with its footers completely above the water level.

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Please visit the small parks. We don't know what's happening behind the scenes
Woodencoaster.com

When CP created the "new land" for TTD that was previously lagoon, they created a coffer dam and drained the water from the area. How parks deal with "water features" and building in them depends on how much control they have over it - but usually they use coffer dams on larger water features and drain the smaller ones (i.e. the water under V2 at SFGAm)

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--George H
---Superman the ride...coming to a SF park near you soon...

hmmm.... yeah the footers are above the water and u can see them if that what ur saying

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Zero-Gravity

*** This post was edited by ColossusHennesay on 1/24/2003. ***

dams for the bigger lakes?? and they just drain the water from smaller lakes?

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Zero-Gravity

If the water is shallow enough, they can make a small retaining wall, dredge out the water in that spot and then pour the footers. Once cured they can then go back and let the water in. They can do it many different ways, it all depends on the cheapest method that gives the results they want.

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Wood Rules!

beastfreak,

that small retaining wall is called a coffer dam, as I stated in my post... ;)

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--George H
---Superman the ride...coming to a SF park near you soon...

Cedar points lake is man made? and V2@ at Great america?

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Zero-Gravity

How far into the ground must footers be inserted to make the coaster stable? Would Magnum footers had to have been put further down than other coasters? Does anyone know how many feet of sand there usually is before you hit actual earth?

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...Agghh, gimme a break will ya?

ah thats a good question i just cant answer it :)

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Zero-Gravity

yeah it kinda helped me understand, and what ur talking abuot is the coffer dam right?

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Zero-Gravity

Well, it all depends on the soil and the strain the footers will face.

I have been told that the footers for Greezed Lightning at SFKK are only being poured like 2-4 feet underground. However by comparison some of Son of Beast's footers are meshed into beams buried 60 feet in the ground.

Shaggy

CP Silly,

Maybe, but they didn't. That's why Magnum is sinking ;)

My understanding is that the footers have to be anchored to bedrock. On Magnum, that would mean getting through the sand and whatever else is there, but that's probably not much more than a regular footer. The depth of the sand is probably not much more than the layer of soil on "regular" ground.

Hopefully I'm not too far off.

Jim

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My K'Nex Coasters
Coming to Wyandot Lake in 2003: Hi-Striker's Revenge

magnum is sinking?

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Zero-Gravity

Shaggy... What you are talking about (way at the top) are piles, not footers. When you have bad soil (as is often the case underwater) piles or piers are used instead of footers. The piles go down to good, strong soil and act as "stilts" to hold up the steel structure. A good example of this is Batman at SFWoA... When the water is low, you can see the round piles which support the rectangular pile cap (a pile cap is essentially a footer that sits on piles instead of soil)

As for how deep... If a footer is used, the depth is dictated by frost. The bottom of the footer has to be below the frost depth (the depth below geade where water freezes). If the footing is not deep enough, when the groundwater freezes and expands, the footer (and the structure attached to it) can be lifted up and damaged. A typical frost depth is around 3 feet - So that is where SFKK's footers are.

*** This post was edited by kip099 on 1/24/2003. ***

X's footers go as deep as 80' in some places.

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Be polite and ignore the idiots. - rollergator
You must be this dumb to ride Viper. -SFGAdv.

Then they are not "footers", they are drilled piers. You drill a 3 foot or so diameter hole down to good soil and fill it with concrete. 80 feet is pretty deep, but not unheard of for a drilled pier (especially in California with all the extra seismic requirements...)