Author Topic: Event Pavilion for Alna Center - Official Reassembly Thread  (Read 31231 times)

John McNamara

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #255 on: March 28, 2020, 10:38:39 PM »
Then is the plan to close up the ends of the building?
Page 14 of this discussion has a February 2nd post by Mike Fox that includes a picture of the East Waterford Corn Shop. I think that is what Mike has in mind.
« Last Edit: March 28, 2020, 10:40:10 PM by John McNamara »

Jon Chase

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #256 on: March 29, 2020, 02:10:02 PM »
Mike,

I think you're right to consider the "extra post" arrangement shown in your mock-up photo, but while the extra 18" (or so) in clearance width this would create at a central "entrance" point is certainly better than nothing, it seems to me that 11'6" is still quite restrictive in terms of limiting the ability to turn a long vehicle toward either end, until fully within the building.  Given the probability of future events where an outside vendor might be bringing in a large truckload of chairs, a portable stage, or sound equipment, etc., I wonder if the alternative of leaving out one post altogether (i.e., creating a 20' wide vehicle access) might be worthwhile in the long run.  Could this be accomplished, fairly easily and without much additional expense, through use of a truss?

A wooden truss beneath the top plate (beam) might be bulky, reducing vehicle headroom significantly, and be somewhat vulnerable to the weather if not sheathed externally.  However, the use of truss rods to increase beam spans or carrying capacity was certainly not uncommon historically, as you may have seen in old mill buildings, railroad roundhouses, etc.

What I have in mind would be essentially similar to a truss-rod flatcar, with a couple of conventional queen post castings spaced beneath the plate, with a two-part truss rod having a central turnbuckle. The truss rod ends would pass through the tops of the adjacent posts, with a heavy bridge washer and nut. It might be prudent to incorporate something to restrict sidewards strain at these locations when the turnbuckle is tightened, such as a short (scrap) length of heavy steel angle with one leg bolted through the plate/beam and the other leg abutting downward against each of the two posts on the "inward" side (i.e., the side facing toward the truss).

Someone among us with a degree in civil engineering may be able to refine this idea, and do the necessary calculations, but if the only investment would be a couple of, say, 12' steel rods, some scrap steel angle and bolts, and some extra car hardware that may already be in stock, it may be a relatively cheap way to gain a considerable advantage (while saving on the cost of the extra post, concrete, etc).  Plus it would have a "railroad-like" visual appearance, creating a subtle architectural focal point for the "entrance." 







 







Mike Fox

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #257 on: March 29, 2020, 05:44:49 PM »
Interesting thought. I'll have to think on that some. If we knew someone that could calculate the span, that would be great. I worry about uneven stress on the posts, because the PT 6x6 may not like that. But I'll draw what you're suggesting and think on it.

My theory is this. We are using 2 2x12s as a header, each 20 feet long. The joints are on the posts, staggered with one 2x12 ending per post. Then, sistered to the outside is a 2x10. These are only 16 feet long. Placing the posts where I did I figured would still provide some support to the one now unsupported joint. I had also thought of another 2x12 sistered to the inside between the posts to support that even more. Instead of having a span of 9' 6" supported on 2 2x12s and a 2x10, we would have a span of 11'6" on 3 2x12s and a 2x10.

Time to google some spans..
Mike
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Mike Fox

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #258 on: March 29, 2020, 06:03:28 PM »
My thoughts are rather conservative. Just with the 3 2x12s, we can span up to 15 feet. 2 2x12 will do 12 feet. By adding another 2x12, that really covered the added distance. Knowing this, I could even go 14 feet with no problem, but then the posts are closer together. We could go 13 feet alright, but would hate to do more that that, in case the snow load ever built up on the roof.
Mike
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James Patten

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #259 on: March 29, 2020, 06:39:18 PM »
I can't imagine any sort of snow or ice load building up that metal roof.  Mine routinely sheds.

John Kokas

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #260 on: March 29, 2020, 07:09:29 PM »
Mike, the easiest means to increase span is the use of a para-lam.  They are specifically engineered for wide space loading and they have a multi-decade history of sucessful use.  And yes you can get them for exterior applications.  I have used several in my own house with the longest span of 22 feet.
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Graham Buxton

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #261 on: March 30, 2020, 07:47:46 AM »
I must be missing something here.  ???

If a large vehicle needs to get inside the Pavilion, why can't it just drive straight in from one end or the other?
Graham

Mike Fox

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #262 on: March 30, 2020, 09:13:02 AM »
Not sure that the West end would be able to be driven,out through. I just figured this little bit of extra width would be good for getting our AA in, and Start brought up a good point to me after I showed him the picture. An ambulance could easily access through that door. Back in or drive in, or even drive through..
Mike
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Carl G. Soderstrom

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #263 on: March 31, 2020, 01:15:22 AM »
Mike. As someone with experience with 11'6" doors in sheds, you need at least 2 feet on either
side. = 15'6" min. If a trailer (any size) has to back in or out that size is a must.
Min 12' height 14' better - maybe a dormer?
I know more $$$, but better now than "Aw shucks!"

Mike Fox

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #264 on: March 31, 2020, 06:20:45 AM »
I had not thought of trailers. But, I used to back a 53 foot trailer through a 12 foor door all the time. My thought was simple, just make it a little wider for our truck. Not sure why we would want to get a trailer in there anyway.

This building was engineered as is. Too much of a change and I would want to have it re-engineered. Adding thickness to the header will make it closer to the ground. It is only 12 feet off the finish surface now, so anything added thickness to that will lower the clearance height.
Mike
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Mike the Choochoo Nix

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #265 on: March 31, 2020, 08:55:16 AM »
another though would be to bolt a strip of 1/4 inch steel plate between the 2x12s. I'm no qualified to do the calculations but i'm sure we have some members who can.
M. Nix
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Bill Baskerville

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #266 on: March 31, 2020, 10:31:31 AM »
another though would be to bolt a strip of 1/4 inch steel plate between the 2x12s. I'm no qualified to do the calculations but i'm sure we have some members who can.
M. Nix
Mike is correct.  It is call a flitch plate.  The simplest is the one described by Mike.  However, they can be a combination of multiple wood beams and flat steel plates.  They are very strong.  The strength calculations can be found online.
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Carl G. Soderstrom

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #267 on: April 01, 2020, 01:01:25 AM »
Mike
It is not the straight back that counts - it is the right angle just inside the door.

Keith Taylor

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #268 on: April 01, 2020, 03:56:22 PM »
Wouldn’t it be easier to just not drive trucks into the pavilion?

Keith

Bob Holmes

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Re: Event Pavilion for Alna Center - Official Reassembly Thread
« Reply #269 on: April 01, 2020, 06:57:24 PM »
Wow, you all are thinking 53' trailers.  Build what makes sense for small groups to unload their gear for an event, and don't worry about it after that.  After all, the pyramids were built mostly by hand!

Bob