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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-20          123094

I have a one acre pond with a 50' X 50' Island in the middle I need to cut grass and landscape. It is about 35' to the edge of the Island from the edge of the pond over water 10' deep. I have thought about steel beams, floating dock mid way, pontoons with ramps. Trying to get out the cheapest way and something I can do with little or no help. Draining the pond will be very diffucult dont want to kill the fish. I turn this over to the great minds I have seen at work on this forum.

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bridge for Island

kwschumm Join Date: Feb 2003 Posts: 5764 NW Oregon   Pics

2006-01-20          123095

The first thing that popped into my head was use 40 foot shipping container with then ends cut off. I'm sure there's a problem with that plan though. It would be ugly anyway. ....

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bridge for Island

dsg Join Date: Jun 1999 Posts: 528 Franklin, Maine   Pics

2006-01-20          123097

"floating dock mid way, pontoons with ramps" would be my guess also. So I think you're on the right track. Or, you could line it with gators and run across their backs.:)) LOL

David ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-20          123099

Tried the gator thing but this is southeast Ga did not take us long to eat the gator tails... You do know gators are tail from eyeballs back. another idea was telephone poles but they are hard to come by. ....

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bridge for Island

dsg Join Date: Jun 1999 Posts: 528 Franklin, Maine   Pics

2006-01-20          123100

LOL, LOL.

David ....

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bridge for Island

countryboy Join Date: Jan 2006 Posts: 26 central Indiana

2006-01-20          123103

sg8
Don't know if you've heard of "Farm Show magazine" (www.farmshow.com). A couple of months ago there was an article about a guy that builds bridges. I'm not suggesting that you buy one but if you can get a hold of the article it might give you some ideas ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-20          123105

CB
Thanks the magazine led me to a company KANSAS STRUCTURAL COMPOSITES INC they have photos. It is worth checking out. I may be able to incorperate some of their ideas in to my final design. Did not think of fiberglass. Water proof wont rot. So is Bud cans. You think budlight cans would float better. My supervisor said if I want to be rich follow him and start saving beer cans. ....

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bridge for Island

Peters Join Date: Feb 2002 Posts: 3034 Northern AL   Pics

2006-01-20          123111

Well is this an aesthetic thing or do you what the least expensive? Cheapest - build a small pontoon raft, 4 plastic barrels and a small deck. Build a ramp for loading your equipment. Tie a nylon rope to the island and another to the shore. All you do is pull your line and move you to the island and pull the other line and park it back on the shore. If you want to get fancy you can build small dock at the shore and another on the island. You just mate the floating section to the dock and it becomes a fish feeding and fishing wharf.
Personally I think a big bridge to a tiny island looks pretty dumb.
Easiest and simple for one person to build the whole bridge would be the Jet float as they are modular and can easily be constructed.
....


Link:   Jet Float

 
Picture Link

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-20          123112

They use the jet float as a pier on a lake at the sub base where I work. I did not know the manfactures. Went to your link and sent them an e-mail. Bridge, ramp, or dock I am looking for cheapest, and something that functions. I would like to drive the lawnmower over cut and drive back. The jet float will last forever and if somehow damaged, sections can be replaced. Sounds good to me hope they put me in the ball park for a price. ....

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bridge for Island

Peters Join Date: Feb 2002 Posts: 3034 Northern AL   Pics

2006-01-20          123116

The original manufacturer was the Canadian military. I believe they sold the first molds to the molder and the rest is history. They are not that inexpensive but cheaper than a special metal bridge and near zero labor to install and up keep. I have not priced them in 15 years so can not even estimate. ....

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bridge for Island

beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-20          123118

2 used pontoon boats and you are across the pond. Not sure how much weight you need to move over the bridge, but pontoon boats might fit the bill. You can get pontoon decks pretty inexpensively if you look around. Anchoring them would be simple enough, spud them or drop anchor. for sure you would want to either spud, or pre-load drop anchors. Pre-loading the drop anchor will make the deck very stable. A little imagination, and dressing to be somewhat appealing to the eye wouldn't be too difficult.

We've put 275 ton cranes on pontoons. Once you spud them, they are very stable. ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-20          123121

I found two pontoons 27'from an old boat for $500. The only info I could get was there was no way to stop them or assure any pontoon from leaking. When under the boat they can be trailered out and drained. That is the only reason i did not jump on it, but that was the cheapest way by far. Build a couple of ramps and I am there. Do you know a way to asure that they will not leak because if they sink water is 9 lbs per gallon over 50 gals and that mean I will need a around a 60ton crane min and a crew of riggers. ....

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bridge for Island

beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-20          123123

Never done it, but have heard of old pontoons filled with foam. They don't even try to keep them from leaking any more, fill them with foam and keep going.

A marina may be able to help. I Don't know what kind of foam was used, and how much bouyancy is retained, but it has been done.

55 gallon drums make great pontoons for docks. Each drum has a bouyancy value of about 3200lbs. That could be an option. All you need to do is frame the deck. I would still recommend pre-loading drop anchors to give the bridge stability. ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-20          123128

OK explain pre loading drop anchors. I was going to tie what ever i do with nylon lines on all four corners, anchored on the island and the dike is this close to what you mean. Bad weather is not a problem, the dike is appox. 12' higher than the island but I can make a landing from cinder blocks and concrete to support the ramp. I like your pond, mine is similar with sea wall and all. ....

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bridge for Island

Peters Join Date: Feb 2002 Posts: 3034 Northern AL   Pics

2006-01-20          123133

Beagle a 55 gallon drums bouyancy is equal to the water it displaces, therefore if it is full submerged it would be about 450 lb. You need 7 barrels to give you 3200 lb. ....

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bridge for Island

Art White Join Date: Jan 2000 Posts: 6898 Waterville New York   Pics

2006-01-20          123135

You might want to look for a curved truss from an old airport hanger. You can do a lot with these type trusses available in wood or steel. Good concrete bases and about three or four run and you should be safe for any thing that might be six foot wide. ....

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bridge for Island

beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-20          123137

Simply said, you pre-load your anchor ties for about the amount of weight each tie would see. If the load influence to a tie down point would be..say..500lbs, you would pre-tension the tie down to about the same or slightly less. The pre-load keeps the float from moving under load, so you have a stable structure. If you used barrels, you tie down at each barrel. The more tie downs you use, the less pre-load (and smaller anchor)is required at each anchor point.

The exact same philosophy is used for floating off-shore drilling structures. You float the platform out, then anchor to the sea bed and draw it down. The draw down pre-load is based on a lot of factors, including dynamic loading from wave influence. The floating platform is then "stable" enough to set drill points. A bunch of stuff you don't have to worry about in your pond.

Of course pre-loading the tie-downs isn't required if you don't mind the bridge bobbing a little as you drive over it.

We did the wall around our pond a couple years ago. It was more out of necessity that appearance. Needed to stop the erosion from eating up the property. ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-20          123141

OK the way you are telling me is that the anchors will be under water and not tied off to the Island. Got ya. Du that was the reason for the barrels. It does not take long for the pond to fill in and all of the dike to wash away. Old carpet works great until grass or sea walls come to bear. ....

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bridge for Island

Chief Join Date: Jul 2003 Posts: 4299 Southwest MiddleTennessee   Pics

2006-01-21          123149

See if you can find an old commercial truck flat bed trailer that has been put out to pasture. Dig a trench for the axles or remove them and have a crane lift it into place or you might try floating the front half with barrels or some other floatation and push it across to the island with a big tractor or bulldozer. We have one on one of our properties that crosses a creek and it works great. ....

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bridge for Island

countryboy Join Date: Jan 2006 Posts: 26 central Indiana

2006-01-21          123152

That last idea sounds the most cost effective to me and old trailers ought to be easy to come by
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bridge for Island

beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-21          123161

OOOPS, sorry, bouyancy of 55 gallon barrel - 420lbs. Was thinking of something else. In any case, they make good pontoons and are cheap. ....

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bridge for Island

Art White Join Date: Jan 2000 Posts: 6898 Waterville New York   Pics

2006-01-21          123163

Chief thats a good strong bridge when built with a tractor trailers frame that's the way we've been using them to put across streams for snowmobile trails. We've even butt welded two for wider streams and cross them with 10.000lbs machines. We set them with excavators on the wheel ends and just extend the front by chains to cross. It might be a frame would also work. Still not as nice looking as just the arches from a roof of a warehouse. ....

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bridge for Island

Peters Join Date: Feb 2002 Posts: 3034 Northern AL   Pics

2006-01-21          123165

Easier to find would be chicken house trusses. I purchased 5 for $1000. They span 45 feet. The top purloins would look like a trellis. You would need vertical structures from the truss to deck, rope, chains, metal or wood. I would think you could build it for a few thousand. You would need a light crane to set them. I rented one for $150 here. ....

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bridge for Island

Art White Join Date: Jan 2000 Posts: 6898 Waterville New York   Pics

2006-01-21          123169

We picked up some from a 60 foot wide building that had an arch built into them of about ten foot on that length. We cut in half to make transporting easier as well as we at the time had no need for them at that length, they were 2by four laminated together five high or deep. They are not the best for NY winter weather but we've had some in about ten years now and still crossing with the 10,000lb groomers. We set them up at about 16" spacing and the bridges are 12 foot wide. The arch for on streams with spring conditions makes it nicer then the flat bridges that catch tree's and limbs and then back up. We were given these trusses as nobody else seemed to want them. We've had oppertunities to pick up more but the open wood is not going to last as long as metal and we are looking at 17,000lb groomers for the new ones and we feel we need more capacity. ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-21          123175

Ok I'm Back. Boy we are making head way now, the flat bed trailer hit the spot. Down here there is a 14' wide burned out mobile home on almost every corner. I can cut the frame to what ever size needed. Any ideas on decking and how to attach. ....

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bridge for Island

Art White Join Date: Jan 2000 Posts: 6898 Waterville New York   Pics

2006-01-21          123197

They aren't very strong to begin with and the metal is light and tough to work with. I'd put what ever configuration together that works off the main rails and test it with the load on it before making the span. If you could have it raised you could cable it underneath for additional capacity. ....

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bridge for Island

countryboy Join Date: Jan 2006 Posts: 26 central Indiana

2006-01-22          123229

hey SG my picture was an old semi trailer not a mobile home frame the semi trailer is built to be load bearing I don't know about mobile home frames ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-22          123238

CB

You are 100% correct the flatbed trailers are rated in tons and would be far superior to the mobile home system. The Mobile home frame would be eaiser for me to cut and weld if I could get a load rating that would be up to the task. The only thing that I should be driving to the Island is my snapper (lawn mower that is). I have seen the size of some of the individuls that live in these mobile units and the frames may carry more of a load rating than we may be aware of. ....

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bridge for Island

Art White Join Date: Jan 2000 Posts: 6898 Waterville New York   Pics

2006-01-22          123252

The home frame I believe would do fine for that load and all the outer rails would be able to be removed. Remember that the homes frame are supported thru out the length. ....

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bridge for Island

Murf Join Date: Dec 1999 Posts: 7249 Toronto Area, Ontario, Canada   Pics

2006-01-23          123266

We routinely have to build crossings for creeks, etc., and have found the two cheapest, easiest ways.

First, the down & dirty, get a flat highway semi-trailer, remove the running gear and drag it over the gap.

Secondly, and IMHO more time consuming, but more "user friendly" is to get two or three OWSJ's (Open Web Steel Joist) made the right length to span the gap. Join them as a single unit by welding or bolting cross-ties in place, then deck with your favourite flavour of decking material. If you have access to them, surplus sign boards work well. They are usually 3/4" outdoor grade plywood and have been well painted. Light steel decking, or even expanded mesh also work well.

Best of luck. ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-23          123290

Art
Do you think Installing cross ties(welding)cut from the part of the frame I do not need would be a proper method to obtain the support.

Murf
OWSJ's maybe found at what kind of company. Can they be purchased in 10' or so lengths and then bolted together.
Is prefab the method for these units.

Peters
This is the answer I got back from Jetfloat maybe in the future they will come stateside.
Dear Mr Padgett,

We have received your enquiry via our UK representative.
Unfortunately we have no dealers in the USA and due to a lack of capacity in
our local sales department we regret to advise that we are unable to assist
you with your enquiry.

With best regards
JETFLOAT INTERNATIONAL
Gesellschaft m.b.H.
Yolande Vercammen


....

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bridge for Island

AnnBrush Join Date: Mar 2004 Posts: 463 Troy OH   Pics

2006-01-23          123291

Bridge? Are you all kidding - the island is 50' by 50'. It seems to me that this is like building an interstate to service a village. IMO you need a cheap push mower and a kids blow-up boat. Place the push mower in the dingy and paddle over. After the first go-round it should take you less than an hour. ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-23          123296

understood, kind of a can I do it sort of thing. I have been using the boat method. Island is Ga. red clay slick as eel slime not easy to load and off load. If I have to build a landing area might as well make a bridge. Both kids moved away and took the raft. ....

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bridge for Island

Peters Join Date: Feb 2002 Posts: 3034 Northern AL   Pics

2006-01-23          123300

I linked both the UK and Canadian dealers on the other post. The link to the US dealers is below. ....


Link:   US Jetfloat Dealers

 
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bridge for Island

kwschumm Join Date: Feb 2003 Posts: 5764 NW Oregon   Pics

2006-01-23          123307

AnnBrush brings up a good point. For an island that small you could buy a cheap used mower and just keep it on the island. ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-23          123320

KW
Ann did have a great Idea do you think the interstate should be two or three lanes. ....

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bridge for Island

countryboy Join Date: Jan 2006 Posts: 26 central Indiana

2006-01-23          123321

I'd hire a Huey to fly in a ZTR and built a 25'x20' pole barn to keep it in! ....

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bridge for Island

Art White Join Date: Jan 2000 Posts: 6898 Waterville New York   Pics

2006-01-23          123322

Speaking of wastes it wasn't but a month ago but the head of the transportation from our congress has a couple of new bridges that will be near record for helping so few as welll as the cost. This bridge is much the same a bit of over kill but so is what our government doing! ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-23          123323

CB
You gotta love America. Not a problem my wife has a good job. ....

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bridge for Island

Murf Join Date: Dec 1999 Posts: 7249 Toronto Area, Ontario, Canada   Pics

2006-01-24          123358

SG, any structural steel or even welding shop can make them up. For that matter you could do it yourself if you can weld.

They can be built in bolt together sections, but aren't very heavy by the foot anyways. Get full length units and just use a rope to pull them into place. I would think 2 or 3 guys could jockey them into position by hand.

They are just a long bent piece of rebar, sandwiched between 4 pieces of angle iron.

Best of luck. ....

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bridge for Island

kthompson Join Date: Oct 2005 Posts: 5275 South Carolina   Pics

2006-01-24          123408

There happens to be a pond with island (two) near me. One belongs to a friend and he built the bridge. Also put a (okay the exact term left me) shelter on it for such as picknicks. That bridge still is an over kill.

The other guys uses a very simple bridge built of wood for his automatic, leather covered, self propelled lawnmower or as some of us call them...goats. I really like his thinking. With this is the lawnmower breaks, you can eat it.

Not being smart but you could put tile in or not and just dump dirt back in to build a road. Since it is a pond I am guessing the water is nor running around the island. ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-24          123412

I have been presented with a plan. 4" X 6" 16'wooden beams knotched and attached with two steel 3' X 6" 1/4" plates bolted through the four by sixes. Built in a roof truss design and set on concrete slabs on each end. If necessary it could be supported in the middle with one 4 X 6 post on each side. The decking would be 2 X 6 4' long. 4' hand rails would be part of the load bearing structure. All Items will be treated. The price is around $800.00 to $1000.00. Anyone see where I may run into problems with this now or down the line. ....

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bridge for Island

kthompson Join Date: Oct 2005 Posts: 5275 South Carolina   Pics

2006-01-24          123433

SG,
I looked back at your orginal post. You said it is about 35 feet to the island. If you use 16 foot lumber are you planning on those slabs making up the length difference or have two joints on each side?
I suggest you get engineer specs on the size of lumber you will need for this span if you go that direction. A 4 by 6 laying down might be sufficent but your decking will itself weigh a lot. Based upon the specs I was given for headers for a shed I think the 4 by 6 is not sufficient.
If you put post in the middle I think they will need some sort of footing so they don't sink in the pond bottom over time.
kt

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bridge for Island

Murf Join Date: Dec 1999 Posts: 7249 Toronto Area, Ontario, Canada   Pics

2006-01-25          123454

Call me a cynic, but, here I go anyways.....

From the very limited amount of detail you can give in 3 or 4 sentences, and IMHO (as an engineer), it won't work.

For lot's of reasons.

First of all, the shear volume of wood itself in the structure. Bear in mind the first thing any structure has to do is hold ITSELF up, before you can even think about loading it further.

Assuming with where you're located, that it will be built using Southern Yellow Pine, and we know that dry SYP has a weight of 45 pounds per cubic foot of wood.

You said the beams will be 4" X 6" X 32' (in total), and there are 2 of them, as well as the decking of 2" X 6" X 4'wide. The beams will weigh about 475 pounds, and the deck another 960 pounds. We're up to about 1435 pounds, and we haven't even thought about the sides, railings, the steel, or the fasteners.

I would guess-timate that the whole structure would weigh in the area of 2,000 - 2,500 pounds.

Best of luck. ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-25          123487

Kt and Murf,

I was given this plan, and did not think it had a chance in hell of working. Just for note he wanted the hand rails made out of 4 X 6's. I work with cranes and weight everyday and this was way out there. I got just the kind of reaction I wanted from this post good logical thinking and guidance toward a workable bridge and have a little fun along the way. I was thinking of 2 X 10's with a plywood sandwich for strenght. Three of these spanning the pond supported in the middle with a post on the bottom. decking to be added with regular decking boards. Please don't quit on me now. ....

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bridge for Island

beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-25          123494

This remains an intersting project.

I am a structural consulting engineer. The facination with bridges traps all of us.

Here's what you have. Considering that you would want the bridge to meet building code, in case you try to sell or someone gets hurt, for an 8' wide bridge, you will need to carry a uniform load of 200lbs/ft. Add the dead load of the bridge girders and deck, by code, your bridge girders would need to carry about 260lbs/ft. This will vary depending on the construction material.

For a 32' span, with a uniform load of 260lbs/ft, your maximum Moment will be 33ft-kips. If you use A36 structural steel, you would have a required section modulus of 20in-3 with lateral bracing to keep the section compact. Since the moment is a function of the square of the span, adding a center support reduces the maiximun Moment to 8.25ft-kips, and the required Section modulus to 4.7in-3.

Here's what it means in Steel. If you had a double girder steel bridge, you would be looking at 2-W10x26 or 2-W14x22 steel Wide Flange Beam, with a braced top flange every 10'. The number after the x is the weight per foot. A good rule of thinb for deflection is the half the span in inches for the depth of the girders. Therefore, the W14 would be a better choice.

Total weight of girders - 1408lbs
At todays market prices - $535 for the steel, plus fabrication costs..

Here's what it means in Southern Structural Pine:
Section Modulus required for No. 1 dense structural lumber 246in-3. You can see the difference the reduced allowable stress makes. To get the required section modulus, you would be looking at a 14" deep x 8" wide timber. More realistically for a timber bridge, you would add the center pier to cut the span in half. To carry the code loading at a 16' span, you would need 2 (no.1 SP) girders 8" deep and 6" wide. Getting close to common timber sizes. These girders again need a deck that will laterally brace the top of the girder.

You may want to look into finding some steel bar joists left over or in a scrap yard. 32' is a pretty common commercial building span. You could get lucky. Again, the seck is an important part of the span, and must be able to laterally brace the joists.

Happy to answer any questions. ....

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bridge for Island

countryboy Join Date: Jan 2006 Posts: 26 central Indiana

2006-01-25          123496

Huh? ....

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bridge for Island

beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-25          123498

Yep, takes an engineer to make a qualified mess out of anything. I stayed out of it for as long as I could. Just had to jump in at some point.

Excuse the engineer in all of us.

Beagle ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-25          123501

I am as much a country boy as country boy is. Beagle what the hell do I have to nail together to get me and the lawnmower to the Island in style. You are right resale value has a lot to do with it. Coastal marsh front is not cheep. A bridge to that island will look good. ....

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bridge for Island

beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-25          123503

Here's the plan-

This post has been great to watch, but has gone a lot of different ways. Give me an idea of what material you are comfortable working with, what is most readily avalable to you, and I can tell you what you need to "nail" together and meet code. I really believe whatever you do needs to be to code. With the lawyers in this country outnumbering the insects, you can't be too careful. The codes are there to protect land owners if you use them right.

I can do it out of steel, wood, or floating decks. It's up to you. Let me know.

Beagle ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-25          123504

time is running short tonight I will gather my thoughs and materials and post tommorow night. ....

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bridge for Island

Murf Join Date: Dec 1999 Posts: 7249 Toronto Area, Ontario, Canada   Pics

2006-01-26          123528

Beagle, I agree 100%, I was just trying to keep it in "Crayon". LOL.

That's also why I suggested clear-span with OWSJ's instead. ;->


Best of luck. ....

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bridge for Island

AnnBrush Join Date: Mar 2004 Posts: 463 Troy OH   Pics

2006-01-26          123529

"Trying to get out the cheapest way and something I can do with little or no help"

I will go out on a limb here: Based on the structural requirements of the bridge you will not get away from this project without spending (when all is done and told) at least 2k. Thats the equivalent of 10 $200 lawn mowers if you assume no present vs. future difference in the time value of money. At this rate you could just buy a new lawn mower every year and leave it unprotected on the island. Also 2k will buy you a nice little John boat setup which you could use to get to the island and then use it elsewhere as well.

Here is another way to look at this:
Assume the bridge setup costs 2k. It's depreciated lifespan is assumed to be 15 years (i.e. in 15 years time you would consider it's value to be 0.00). Assume an annual depreciation of 20% in year 1 and 19% in year two and 18% in year three and so on. You could use your own estimates for this kind of sturcture - I assumed that in 5 years it will have lost approximately half it's value, if you think that's steep ask your accountant they will tell you it's not nearly a valuable as you think it is. The first year of mowing will cost you 400 dollars in depreciated bridge costs alone - say you mow 5 times, that's 80 bucks per mowing. In year 2 it will cost 304 dollars in depreciation costs or just over $60 per mow and so on. My point is that a bridge structure is a comparitvely expensive option and that's not what you asked for. Ask your wife if she thinks you need a 2000.00 bridge - I know what I would say. ....

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bridge for Island

Murf Join Date: Dec 1999 Posts: 7249 Toronto Area, Ontario, Canada   Pics

2006-01-26          123538

And here's yet another way to look at it:

Put a nice bridge over to the island $3,000
Build a nice gazebo on the island $2,000

Have a nice island you can walk to, with a lovely gazebo on it as a landscape feature, and have an appreciation of maybe $25,000 for a mere $5,000 investment.

I know what my wife would say, and boy am I ever glad my wife doesn't make the financial decisions. ....

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bridge for Island

kthompson Join Date: Oct 2005 Posts: 5275 South Carolina   Pics

2006-01-26          123542

Murf,
gazebo was what I could not remember my friend built on his island.

SG, since you are in Georgia you will need to add electricty to that for a ceiling fan to keep it sort of cool and the insects off. Also put in grill what a neat get away it could be.

My friend's island was used for their daugther's wedding. The wedding party on island and guest were not. Great set up.

kt ....

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bridge for Island

AnnBrush Join Date: Mar 2004 Posts: 463 Troy OH   Pics

2006-01-26          123550

I guess it depends on whether you are in the maximist or minimist camp. Looks like I am one of those in the latter and from where I stand looks like there aren't many of us ;) ....

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bridge for Island

SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-26          123558

Ann
you are determined to get me behind a push lawnmower. You think I am nuts, I have not discussed this with the wife. She works with an accounting firm you and her would have me swiming to the island with hand shears.

Murf
a gazebo the same size of the Island I would not have to cut anything, might as well add a bar. With the bar I would surly need hand rails on the bridge.

KT
I still have one to marry off so the wedding party sounds good to me.

Beagle
Went to the local buy any thing store, met a guy that builds docks. He has two 55' 12" X 12" treated beams that he builds docks from. I can cut them to suit. He gave me the number of a person who may already have beams cut to size I will check with him tomorrow. At the store this guy had bought floats for a dock and his customer backed out. They are 3' x 4' by 3' high thick plastic, you for some reason cannot use styrofoam for docks any more. $90 for the floats apiece the beams $140 to $150. Is this a good start. The floats are if I need a floating dock. Might get the foats for future use.
....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-26          123562

I think we can make this work, and have a decent looking bridge. The 12x12 timbers are border line for the 32 foot span, whick means they are in the stress range, but will probably feel soft under load.

What I would suggest is doubling the 12x12 for the center 23 feet of the bridge. If you can picture this, span the 32 feet with the 12x12 timber, then reinforce the BOTTOM of the center 16 feet out of the 23 foot drop. You can use the whole 23 feet (recommended) if you want. We can get a good shear connection between the two timbers with through threaded rods on 24"C/C, and three rods at each end. In other words, your bridge girder will be 24" deep for the center 16 or 23 feet, whatever you decide.

If that sounds good for the girders, we can start looking at the stringers and deck. ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-26          123564

Ok lets say I have two 12 x 12 33long side by side spaning the to the Island. you lost me with the reinforcement 16' and I dont have a clue about the 23'. were you thinking I was only using one 12 X 12? ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-26          123567

Ok, let's try again. you need to but both 55 foot timbers. You'll have 2 12x12 timbers spanning to the island. For the center 16 feet of the 33 foot span, you will add another piece of 12x12 to the bottom of each girder. So for the center 16 feet, the girder will be 24" deep. We'll take a pice of what we cut off the 55 foot timber and add it to the bottom for the center 16', through bolted to the 33 foot long timber.

33'
Land--------------------------------------Island
--------------------
16'

Side View of Girder

Hope fully the diagram above helps. The girder is 24" deep for the center 16'.
....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-26          123568

The little skecth didn't work. All got left adjusted. The girder is 12" deep for the first 8 1/2 feet. 24" deep for the center 16', and 12" deep for the last 8 1/2 feet.

That's what I was trying to show. ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-26          123569

A picture is worth a thousand words. The light bulb is now on. Now that I am up to speed, let me talk to the owner of the lumber tomorrow. Boy we went through some changes on that one here. LOL ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-26          123573

Just so you understand, we can make that work out of the 2 55' timbers he has available.

If that works out, use 4"x6" stringers at 2'0 c/c between the girders, with 2x8 deck boards accross the stringers for the length of the bridge.

Beagle ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-26          123575

we are talking about two different guys. The guy with the 55 footers does not want to cut them but he will if this other guy does not work out. ....

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bridge for Island

shortmagnum Join Date: Nov 2003 Posts: 848 Wisconsin   Pics

2006-01-27          123592

Beagle, If you have Powerpoint or even MS Paint you can draw the plan and save a jpg image that can be posted with your pictures. I did it for a logging grapple.
Dave ....

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bridge for Island

beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-27          123600

Thanks, I didn't think of that. Would definitely be easier than babbling back and forth. It's that whole picture and a thousand words thing. ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-27          123618

Went by the lumber man and ordered two 12" X 40' treated poles to be delivered next week. Each are marine treated and very nearly straight. They start out 13 1/2" and taper to 8 inches. gone for the weekend. ....

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Art White Join Date: Jan 2000 Posts: 6898 Waterville New York   Pics

2006-01-27          123644

You should have a good base to sit them on so they will stay dry. ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-28          123662

I'm sure you understand that the tapered poles won't span the 32'. Curious as to what you are going to do with them. With the taper, we could use them as masts for a cable stayed span, but not sure that's what you had in mind.

Feed my curiosity. What ya going to do with the tapered timbers? ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-30          123786

They are 40'ers you dont think that we could cut of the last 8' and have something that would work for the span.
They are treated for marine use in salt water. This taper would make them 13 1/2" on one end and 10" on the other. Not to late to turn off the order. ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-30          123787

They won't free span the 32'.

We could make them work if we add a center pier and span them 16', but not 32'.

We needed a 24" deep girder for the center of the span if we go the whole 32'. Thats why I was doubling up the 12x12" timbers we discussed last week. The taper makes them difficult to double up.

If you would like a sketch of the girders, let me know and I will post one to my pictures this evening. I don't think the words are explaining what you need very well. ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-30          123789

sounds good to me, just wondering, 40' wont span 32, you are correct i need a picture. ....

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kthompson Join Date: Oct 2005 Posts: 5275 South Carolina   Pics

2006-01-30          123790

SG,

I thought the same thing you asked but reread Beagle and realized the word "free" I had missed.

You do realize when you get this built we all will be expecting pictures on what you finally did and to be invited for a cook out to test it. Please, not July or August.

kt ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-30          123792

I have all plans of pictures and updating to a premium member. This is a geat forum. You dont have to wait for the bridge for a cook out I do love a party. Doors open, pond is full of fish. ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-30          123799

OK, check out my picture 20. Very rough sketch of the side view of two different bridge concepts. One is a 32' free span with 24" deep girders, the other is for 2-16' spans, requiring 12" deep girders.

Take a look at the sketch and see if we are together so far. We can continuously add detail as we get further through this.

I had to reduce the sketch, hopefully you can still read it.

Beagle ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-30          123808

beagle
Not catching onto the Termonology was killing me. The drawing is highly outstanding. I will look into some beams now that I got "free span" in my head I think that is the way to go. Two 32' X 12" X 12" and two 16' X 12" X 12". If I have paid attention this is the minimum that I will need. Timbers or poles are all that I have seen so far. This is why you ask questions, keeps me from spending all of my wifes hard earned money.
KT
Thanks for the pointing out the word "free". Still did not have a clue until I saw the drawing. ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-30          123812

OK, the 2 - 55 foot 12"x12" timbers would work for the 32 foot free span sketch. Cut each timber to 32 feet, then take the 23' we cut off and add to the bottom of the 32' piece to create the 24" deep girder. That's what my 32' free span sketch shows.

The through rods I talked about last week is what connects the 2 12"x12" pieces together to create the 24" deep girder.

How are we doing so far? ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-30          123817

MY fault the 55'ers are also tapered poles intended for building docks. I will look for beams. The local lumber store had 25 footers but they maybe able to help me out.

POLES ------ round or round and tapered

BEAMS ------ square or rectangle

dont give up on me. ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-01-30          123822

I think once we get our vocabulary figured out, the rest will be easy.

If you want to go with the 2-16 foot spans, it might be easier to get the materials and keep the bridge light. The center pier would be some work, probably 4 "poles" jetted into the pond bed about 4 feet, with 2 2x12's as a pier top across the tops of the poles. The sketch kinda shows the pier for the 2-16 foot spans.

Tell me again, what is the heaviest piece of equipment you want ot move over the bridge?

We're not going anywhere. ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-01-30          123828

A 300lb lawn mower and 200lbs of me at the most at one time. I would rather not do the post in the pond thing if we can get around it spaning the 32 ft sounds good. I'm in Ga. we do everything slow, it is hard to read as fast as you write. ....

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bridge for Island

cheezy1963 Join Date: Apr 2005 Posts: 9 ok

2006-02-20          124850

I used 4' 1/4 wall square tubing for my bridge. My island is about 40 x 40 and the span is 28 feet. I had a local pipe bending company do all the bending for the arch which gives it about 2' rise. ....

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kthompson Join Date: Oct 2005 Posts: 5275 South Carolina   Pics

2006-03-08          125811

SG,

Okay, it has been over a month and you don't have snow for an excuse. So is the bridge built yet?

....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-03-08          125815

Cheezy

What weight limit do you think your bridge is good for?
How did you make the attachments for the decking? Do you have any specs?

KT

33' 12" X 12" treated timbers are very hard to find have to be special cut, and they want an arm and a leg. I was looking for the cheapest way or the less expensive way to have a bridge. Right now I have the cheap push lawn mower on the Island that should make Ann happy. You should have seen that show with the lawn mower in the boat and the off load evolution in that wet red clay. My wife was in shock and awe after putting eyes on me. I should have taken pictures you would have loved it. I hope to have the beams ASAP. ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-03-08          125818

If either of you is interested, I can tell you what the load capacity of the arch is with a little more information. With an untied arch, the foundations could govern the capacity of the arch. If the arch is tied at the bottom, the capacity is internal to the arch structure.

If you let me know if the arch is tied, and if not what the foundations are, we could determine the capacity.

Maybe someone did it for you before it was built. ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-03-08          125827

I am intrested but dont have the info. ....

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kthompson Join Date: Oct 2005 Posts: 5275 South Carolina   Pics

2006-03-08          125832

SG,

Cheezy? I am dumb. In southern what does that mean?

It is good to know that at least there are others who don't get things done as quick as they want, besides me.

Will be looking for finished pictures.

kt ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-03-08          125836

KT

Aint cheezy the guy that has the pole bridge. I read his post slo-----wer this time and it appears that he used a 4 foot dia tube with 1/4" thick walls. Is that correct. That is one hell of a bridge. Steel is 40lbs for 12" X 12" x 1" thick. So the way I got it figured one span is 11,200lbs of weight. I dont know it My 2425 farm pro is up to that. ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-03-08          125840

Wait a minute. He used TS4x4x1/4 wall tube for his girders. Not counting the added length for the arch, the girders weigh 342 lbs each for a 28 ft span. TS4x4x1/4 wall tube weighs in at 12.21lbs/ft.

The capacity of the bridge isn't necessarily directly related to the weight of the girders. Assuming he used two girders, the bridge weighs 684lbs, plus the stringers and deck.

Relatively light actually. ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-03-08          125842

What is TS is this expanded metal? 4' x 4' X 1/4" thick square tubing. I may need another picture Beagle. ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-03-09          125852

You know, I went back and looked at his post. It does say 4', or 4 foot 1/4 wall tubing, but I think he meant 4" tubing, which is a common size in square tubing, so I used that for the weight. I don't think he built a 28' span bridge out of 4 foot deep tube.

TS, or more recently HSS, is used to designate cold rolled steel tubing. The old TS designation was "Tube Steel", the more recent HSS designation is for "Hollow Structural Sections". Just a sexy industry designation for steel tubing. ....

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cheezy1963 Join Date: Apr 2005 Posts: 9 ok

2006-03-19          126311

Sorry guys....I made a few errors in my post. First of all, I used 3 inch OD .25 wall square tubing for my lower rails....not 4 foot :) My bridge is 24 feet long and 46 inches wide. The upper rails are made of 1.5 inch OD .1875 wall square tubing. The cross planks are made up of treated 2x6 wood. I looked for my original specs but couldn't find them so I went down to the pond and measured. I built it about 2 years ago and believe it cost around $1100 to build it. ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-03-30          126925

Hey Beagle

check out this link and see if it makes any sense to you for my project. ....


Link:   

Click Here

 
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bridge for Island

beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-03-31          126937

Pretty good stuff, could be a solution, but also could be pricy, be carefull of a couple things when picking a bridge type:

Un-tied arch bridges rely heavily on their foundations for capacity. The foundation needs to be designed to accomodate the horizontal thrust from the arch. The bridge structure will be lighter and less expensive, but you will pay for it in foundation cost.

Tied arches are extremely efficient, and require less foundation work. There aren't horizontal reactions to worry about in tied arch bridges.

Pick a wood bridge with the least number of pieces in it. Connections of pieces in woof structures is where all the deterioration starts. The fewer the number of pieces, the less places for the structure to rot.

When picking a bridge type, make sure you know what kind of foundation you need for your span, you could end up putting a lot of money in the ground.

....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-03-31          126969

I see what you mean, where all the bolts hold the boards together will hold moisture and go down hill from there. I did notice the step type foundaions that they were using. Any way all those boards add up and will take some labor (several people).

I have priced several beams and trying to find the best for the cheapest. You and I had discussed using 12" by 12" beams I was going with the 35' span with a 20' brace. Would it make a great deal of difference if I used a 10" X 10" beam. The distance to span is 32' I was going with 35' as to have enough to set on the footing. ....

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Gary Lenzmeier Join Date: Posts: 1

2006-03-31          126974

I had a situation like that a few years ago. I had to transverse a drainage ditch. I did it with a pair of used utility poles which I streched across the ditch. I think the distance for that one was 32 feet. Once I had them in place I screwed regular treated 5/4 decking across the entire span. Although this worked and I did drive my JD 212 across it, I decided to make one set of peers midway which really strengthened it. I did that with a pair of 4 X4s which I extended into the water then fastned to the bridge. It is still standing and I have not had to perform any maintenace. Best part it didn't cost me that much especially since all the decking I already had.

Gary ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-04-01          127002

SG, I'll check the 10' x 10" if you can tell me what type of wood it is, (ie southern pine). THe allowble stresses vary quite a bit between species.

Remember we are doubling up the girders at the center, so we sould have a nominal 20" depth where we are doubled up.

The other problem with wood structures is "creep". Wood tends to "stretch" over time when under load, so we want to stay in a low stress range. Otherwise your bridge will have an ugly sag in it after a couple years.

Se if you can find out what type of wood the 10" x 10"'s are, and I'll check them. They will probably work.

Beagle ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-04-03          127119

SOUTHERN PINE down here there are very few other kinds. LOL ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-04-04          127142

Thanks, I'll check itr for southern pine. I trust you still have the sketch of the girders we drew a couple months ago.

I'll let you know on the 10x10's. ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-04-04          127200

Beagle
The sketch is #20 on your pictures. I was going to make the support beam 24'. Is that correct? ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-04-05          127227

That is what we needed with the 12x12 timbers. Give me until noon today and I'll let you know what you need for 10x10", southern pine.

Got a couple thingws we need to get out this morning, them I'll check the 10x10's. ....

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beagle Join Date: Jan 2004 Posts: 1333 Michigan   Pics

2006-04-05          127230

10" x 10" Southern Pine timbers will work at the 32' span, with 24' of double timber girder as shown in Pic. 20.

Beagle ....

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SG8NUC Join Date: Jan 2006 Posts: 579 g   Pics

2006-04-05          127275

Thanks beagle I'll get to work on the orders. ....

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