Greetings;
This project is more of an installation of sorts. I call the structure "Furniture" because it seemed like I was building a boxed Ikea product (with better instructions - of course), and because I could dismantle it and install it in another location. The parts fit together in many different configurations with only minor changes needed.
Well, maybe just watch the two flash video's and let me know what you think.
I am most interested in making connections with people/organizations that are also passionate about old building, and how we can (and are) interact with them.
This is worth a look, I think. I wonder why more student work isn't posted here .
The PDF page is handsome and informative, and the presentation video is marred perhaps only by the insertion of crisp photographs which, nevertheless, lack the perfect timing, and the laser pointer (?), which I'm guessing was present at the live event. Still, it's an engaging and even heart-warming look at the efforts of the fledgling to nest, temporarily, within the parental mammary -- after diligently patching up the sheltering fabric of the Old Cow ?
Because the project as presented is incomplete, perhaps it's best to wait for more photos before judging the result. In the meantime, the assembly video is entertaining and informative; not many artisans are willing to document the onsite erection of untested components for all the world to see. If for this alone Mr Mahoney deserves a hand, no ?
As a long-time proponent of KD and folding "furnitecture," and of course a big Wright fan, this project seems designed to appeal directly to me. I wonder how others will perceive it. Anybody ?
I read the pdf and watched the assembly video. I really enjoy these kit of parts projects. I find it very satisfying to watch each unique piece fit into its own specific spot, though I am also aware that some of your components can be used in varied ways. I appreciate that you aligned the decking with the staircase, visually this is very appealing.
I am curious, what made you place one of the legs inside the staircase as opposed to the extreme point? Placing it at the extreme (bottom of the hexagon when viewed in the assembly video) seems to be the natural location for this member. As it is shown, you have a slight instability in the frame, which is evidenced by the rocking motion as you climb the steps. This is overcome by the weight and shape of the frame, but you haven't really addressed it explicitly.
The front leg - I really wanted that whole front end to cantilever without the help of any leg. I realize given the non bolted nature of the frame would really not give me the moment I needed to suspend that weight. I used a small leg (smaller than the other 4) and "hid" it just out of view. I don't have a shot that shows it specifically, but you can look at this rendering and see what the effect is like.
I was testing two things with this mock: 1- how well a double fillet would do on the stringer side of the .25" plate (apposed to a messy fillet on the foot side of the tread) - It passed that test. 2- the proportions of the treads for a comfortable assent/descent - it passed as well.
I'm glad to hear you considered the issues. I realize that your installation isn't permanent and I can only imagine you aren’t allowed to cause any damage to the existing structure, so it is understandable. Were you allowed to operate freely, a classic way to resolve the instability problem would be with some sort of tie back. You’ve got a short cantilever, but it is your main access point, so it basically sees your maximum load. Most likely the easiest way to solve the issue would be to bolt the column bases to the concrete. You could run a quick number, but it is hard to imagine a scenario were the resulting tension force would exceed the yielding of the bolt or the breakout strength of the concrete.
In the actual stair, you are relying on a moment connection, which is one reasonable solution. An alternative would be to create a truss by adding a brace to complete the triangle suggested by the cantilevered stair frame. This would greatly increase the stiffness of the stair, but of course the aesthetic may be unacceptable and is something you’d need to consider. Otherwise, increasing the depth of the tread brace will also increase the moment of inertia and thus the stiffness.
Re. bolting to the concrete: Well let me say everyone is telling me to bolt it to the concrete (even the property manager). There is two reasons I won't do it: 1- how much concrete (depth) actually exists is unknown. Now being at Taliesin for 3 years, I know that there was no standard when it came time to pouring slabs etc... I can only assume and 1" or 2" poured over some earth and crushed sandstone. 2- I am trying not to do any modifications to the existing site (other than repairing the existing fabric).
At this point the movement on the stair cage is minimal. Once the final tension cables are installed, the stair, and the weight of the top deck the movement should be almost null. If I still need more 'umph' on that cantilever I could increase the bolt detail on the fascia, which anchors into 1.5" TnG black locust decking and the steel frame. Currently the bolt detail on the fascia is minimally structural.
I don't think I fully understand what your are suggesting for the stair? Are you speaking of the stair cage, or the ship stair (to the top decks)?
Ok I understand your concern for the site. My point of brining up the stability was really more academic than a specific request. Just encouraging you to consider the issues and giving a little insite into how the issue might be resolved on other projects, which sounds like your professors have also discussed with you. Stability of a structure is an issue that needs to be considered both in the final constructed form and also in the partially constructed state. Please don't take my posts as anything more than commentary and discussion.
My comments about the stair were refereing to the lower stair that you use to climb onto the lower platform from the concrete floor.
Yes keep the comments coming! I like the feedback.
It would be nice If I could put some type of non permanent epoxy on those feet, which could act as an anchor...hmmm.
I'll think about the stair cage truss...but I'm still a little unclear of the detail your describing.
Heh-heh -- "museum wax" is some sort of sticky but harmless substance that is placed under smallish vulnerable objects to prevent damage during seismic events, etc. It's doubtful that this strategy would work at large scale.
I can fully sympathize with the self-imposed "hands off" free-standing requirement. I once built an interior furniture-object superstructure that was attached to an existing cast-iron radiator, and otherwise stabilized by elements that touched opposing walls.
I can't read what's going on at the top; what is the red-colored vertical pipe doing ? Is that an existing element ?
In the small gray "signature illustration" of the whole construction there appears to be a perimeter handrail at the top; if this ends up just under the building's two cross beams, perhaps a judicious bit of blocking there will be enough to transfer down-force through the rear leg to the floor, and substitute for the fastening of that leg to the "slab" (I hesitate to call it that if it's an inch thick) ?
SDR - I think I understand. Create a relationship between the buildings existing 8x8s and the slab. Create a member that would be activated once the force is applied to the stair cage (185 pounds ;-). I don't think the relationship would have to be that pronounced...as the 'movement' is minimal-currently.
Continuing with a critique of the work, I have taken the liberty of copying one of the illustrations from the presentation. I must say my eyebrows tried to disappear within my (receding) hairline when I saw this dog-leg beam
which seems to give new meaning to the term "structural bent" ! But it started me on a quest to map out the alternative possibilities, and to play detective at what the process might have been that led to this choice. I've made some diagrams, in which (A) represents the chosen solution, and (B) is the most obvious, "safe" (if rather unimaginative) alternate.
Why would (B) not do, for Mr Mahoney's purposes -- no fear of deflection, no difficult-to-measure (and resist) combination of bending and torque at the connection between beam and node ? Why invite trouble, in other words ?
One positive attribute of the chosen support point of Mr Mahoney's hexagon frame -- the post, and the connecting node -- is that it neatly occupies what would otherwise be wasted space, between the hex figure and the cylindrical envelope surrounding it. Another advantage is that the post and node do not interrupt the hexagonal surface plane at all.
Also, it seems that one of Mr Mahoney's goals with his structural kit-of-parts is that it be reconfigurable to other uses -- presumably ones of orthogonal, rather than polygonal, plan shapes. To this end, the node is made with receptacles arrayed at 90-degree intervals. The chosen plan (A) permits the use these universal nodes, while (B) would not. So, how about this compromise (C) ?
Well, that solves the node problem, but not the problems mentioned in the previous paragraph. Does that explain why it was rejected ? As a final attempt to solve all the problems (as I see them), I show (D), where the sides of the hex frame are continuous, and are clamped or otherwise fixed to the support node, needing only to be connected at their ends (as in the system presented). Here, the beam is cantilevered from the post (wouldn't Mr Wright be pleased ?) and rigidly fixed at right angles to the vertical.
Incidentally, I am also puzzled by a comment made in passing during the presentation, in which Mr Mahoney says something to the effect that the "hexagonal design" will contribute to the structure and "hold tight" the connections (if I understood correctly). I wonder what attributes of a hexagon-shaped frame would be superior in this regard, over a rectangular one. As far as I know, only a triangle presents such an intrinsic rigidity -- but I may have missed the point.
I will be interested to know if I have followed the designer's thinking with any degree of fidelity -- and I hope to be forgiven for trying to second-guess his methodology.
[For ease of reading, here's the whole thing in one piece]:
Continuing with a critique of the work, I have taken the liberty of copying one of the illustrations from the presentation. I must say my eyebrows tried to disappear within my (receding) hairline when I saw this dog-leg beam
which seems to give new meaning to the term "structural bent" ! But it started me on a quest to map out the alternative possibilities, and to play detective at what the process might have been that led to this choice. I've made some diagrams, in which (A) represents the chosen solution, and (B) is the most obvious, "safe" (if rather unimaginative) alternate.
Why would (B) not do, for Mr Mahoney's purposes -- no fear of deflection, no difficult-to-measure (and resist) combination of bending and torque at the connection between beam and node ? Why invite trouble, in other words ?
One positive attribute of the chosen support point of Mr Mahoney's hexagon frame -- the post, and the connecting node -- is that it neatly occupies what would otherwise be wasted space, between the hex figure and the cylindrical envelope surrounding it. Another advantage is that the post and node do not interrupt the hexagonal surface plane at all.
Also, it seems that one of Mr Mahoney's goals with his structural kit-of-parts is that it be reconfigurable to other uses -- presumably ones of orthogonal, rather than polygonal, plan shapes. To this end, the node is made with receptacles arrayed at 90-degree intervals. The chosen plan (A) permits the use these universal nodes, while (B) would not. So, how about this compromise (C) ?
Well, that solves the node problem, but not the problems mentioned in the previous paragraph. Does that explain why it was rejected ? As a final attempt to solve all the problems (as I see them), I show (D), where the sides of the hex frame are continuous, and are clamped or otherwise fixed to the support node, needing only to be connected at their ends (as in the system presented). Here, the beam is cantilevered from the post (wouldn't Mr Wright be pleased ?) and rigidly fixed at right angles to the vertical.
Incidentally, I am also puzzled by a comment made in passing during the presentation, in which Mr Mahoney says something to the effect that the "hexagonal design" will contribute to the structure and "hold tight" the connections (if I understood correctly). I wonder what attributes of a hexagon-shaped frame would be superior in this regard, over a rectangular one. As far as I know, only a triangle presents such an intrinsic rigidity -- but I may have missed the point.
I will be interested to know if I have followed the designer's thinking with any degree of fidelity -- and I hope to be forgiven for trying to second-guess his methodology.
that is a great critique, I really like how you break down the process. To tell you the truth, I also had a very similar reaction when i first saw the bent beam but didn't mention it. Thanks for highlighting this issue, and for positing some very effective alternatives.
If I am indeed understanding the diagram correctly, It should be noted that the final solution (D), will introduce some eccentricity of load into the columns(legs) of the frame, due to the beam being offset. This will be most critical at the time of construction before the frame is completed, which brings us back to my previous point about analyzing a structure both in its completed state and in its partially constructed states. Would it not be possible for the beam to continue over the top of the leg, thus eliminating the eccentricity, or will we have strayed too far from the tinker toy origins?
It is possible that the diaphragm created by the decking, if properly connected, will act rigidly, providing stability and stiffness to the frame, but I agree, the hexagonal form is not inherently stable.
Thanks, Synergy. To your point: true -- but that can also be said of (A), can't it ? In all cases, stabilizing the posts (columns) by whatever they are connected to above, would presumably overcome the problem ? (The further up [i.e., the more remote] that connection is, the less force would be placed upon it; a handrail above the second-level platform would presumably provide enough leverage to keep the columns vertical -- to say nothing of an identical second platform itself ?)
The thing that troubles me about the majority of the slip-fit connections in Mr Mahoney's "kit" is that they are not deeper in insertion than the dimension of their cross-section; thus, they seem prone to loosening when bending forces are applied. (This does not seem to be the case with the vertical, cylindrical connections.) Call me "Mr Overkill." Another question I have is whether the system depends upon a complete array of tension cables, some of which are in evidence in the construct. Are these a "fix," applied as and where the need arose, or were they an integral part of the system ?
I note that the complete assembly of the lower platform includes a second steel edge member, this one the full length of a hex side, which is applied over the wood deck boards (which, being laid loose and "dry," will not have the full effect of, say, a plywood diaphram, will they ?). These steel "caps" may be well-fastened to the steel frame below. If so, this effectively answers my original question. . .
Wow - thanks!
This is good stuff.
I'm just back from a little three day camping trip (to that great crack in the earth). I'm looking forward to reading over this more thoroughly so I can be sure to give the appropriate response to your thoughtful/thought provoking critique.
-Russell
Hey great! I was enjoying this discussion before it went a little cold.
SDR,
In answer to your question above, you are completely right, the unattached decking will not provide any rigid diaphragm action. To get rigidity out of this system we would need to attach the decking to the frame, and probably run some steel strap ties between the decking members, perhaps in a Z or X pattern to get something really solid.
More cables ? Even if every board were attached at every point where it met metal, the boards could still slide past each other, defeating the attempt at turning the wood into a structural diaphragm. The boards would have to be glued to each other -- making the system a lot less portable ?
But I'm not sure yet that the lack of rigidity in that plane is significant, here. I'm curious to see what Mr Mahoney thinks of our dissection.
Not cables, but flat strap ties between the decking boards. Along the lines of what this image shows, except in place of the metal studs, we would have our decking, lying in a flat plane. The strap are usually 3" wide material and 16gage thickness I believe, though I believe there are options depending on the specific demand. You are right though, it is intended to provide resistance from the boards sliding past one another.
Hello SDR:
The age old question A vs B vs C vs D...
D works for two reasons:
1 - you are correct with the assumption that the 90degree construction allows for the future use to be an orthogonal option. So C or D would work equally well.
2- What D does that C does not is allow for the maximum sq. footage. The nodes occur almost to the full inside diameter of the existing masonry in the tower. If I were to use option C it would shrink the floor sq. footage. In a 9'3" diameter cylinder I was looking for maximum floor space.
- How do I post pics inside of the post? Do I use HTML?
The code appears in very pale gray at the bottom of the posting box -- I can't read it. The formula is, add after it, no spaces. If your image is more than 420 p wide, reduce it by adding "width=420" (no quotes) to the end of your URL, with one space, in front of the [/img] (no space).
What you write is in line with my supposition. How was the Big Hole ? I've never seen it. Are you back in the shop, with the ship stair ? What part of the Taliesin shop is al fresco ? Good equipment ?
The formula is, add {img} in front of your URL, and {/img} after it, no spaces -- but use these brackets []. If your image is more than 420 p wide, reduce it by adding "width=420" (no quotes) to the end of your URL, with one space, in front of the [/img] (no space).
Synergy:
Regarding the decking. I'm not sure if I understand the strapping technique. I can tell you when I installed the fascia, and bolted the frame, 1.5" TG locust, and the 3/16" steel fascia the whole floor became very rigid.
Here is a detail: http://www.russellmahoney.com/images/fascia_det.jpg
Can you explain more about strapping? Can this be a possibility to distribute that load from the stair cage?
Thanks
Russell
Synergy:
Regarding the decking. I'm not sure if I understand the strapping technique. I can tell you when I installed the fascia, and bolted the frame, 1.5" TG locust, and the 3/16" steel fascia the whole floor became very rigid.
Here is a detail:
Can you explain more about strapping? Can this be a possibility to distribute that load from the stair cage?
Thanks
Russell
Synergy:
Regarding the decking. I'm not sure if I understand the strapping technique. I can tell you when I installed the fascia, and bolted the frame, 1.5" TG locust, and the 3/16" steel fascia the whole floor became very rigid.
Here is a detail:
Can you explain more about strapping? Can this be a possibility to distribute that load from the stair cage?
Thanks
Russell
Synergy:
Regarding the decking. I'm not sure if I understand the strapping technique. I can tell you when I installed the fascia, and bolted the frame, 1.5" TG locust, and the 3/16" steel fascia the whole floor became very rigid.
Here is a detail:
Can you explain more about strapping? Can this be a possibility to distribute that load from the stair cage?
Thanks
Russell
Russell, when you post images, put in 'width=400' before the final [/img ]. Otherwise it may be too big.
The strapping is designed to create rigidity in the decking for in plane stresses. For example the decking will certainly resist vertical loads from you standing on it, but try to image a heavy stress from a twisting, torsional action on the whole frame, can you imagine how the boards might shift and slide relative to one another? The idea is to get the decking to act as one rigid system (though this isn't always a benefit in every case, it can be a useful quality). You would lay the straps flat, and perpendicular to the decking and attach it to every piece of decking. I would also lay one or two straps diagonally, like the image I posted above (Imagine the image is rotated so that the vertical studs were your decking, and that there was no space between them). The net effect is to create a rigid triangle, which will not deflect in any planar direction. The triangle would be made of two legs of strap and one leg of decking. The exact strap layout would require a little thought since the deck shape is not a simple rectangle, You could attach the straps to the bottom of the decking.
To be honest, this concern is really more academic, as it is very unlikely that your structure would see this kind of load, which would generally result from wind or earthquake. With a properly working rigid diaphragm, if you push on one side or leg of the frame, you will engage the entire structure and all the legs, instead of the single element.
On the other hand, you could ignore any contribution from the decking and return to simply relying on the frame to provide rigidity. In this case you have options of forming closed brace conditions (ie. trusses & triangles) or moment connections. Currently your system is something of a hybrid, but basically relies on the eccentric moment capacity of the members and connections, which is acceptable given the small loads, but would not, generally, be a solution used for larger structures.
While we're waiting for construction to be completed, should I raise the issue of "adaptive reuse of (an) historic structure," the putative subject of the thread ? Russell, did you have questions or comments about this ?
SDR - What is to be done with these historic structures? Should they be restored to their "prime" and be treated like a museum? Should they be adaptively reused for something more appropriate for the time?
- I'm stuck here: I love old building, especially when they have such a rich history, but I also want building to have a function... Does a structure have a soul? What would it be happy doing for the next 100 years?
All good questions, for sure. Starting with your own intervention, the combination of tenderly-applied repairs, and a (literally) harmless insertion, seem wholly appropriate. It would tickle me to know that the useful "furniture" you are installing in the milk room might stay in place for years or decades, serving successive members of the ever-evolving Taliesin community -- even though you have evidently designed it to be removable on 24 hours notice.
If man has a soul, then his "trees and rocks" may be more likely to having them too, than the mere furniture of nature. More to the point, we might ask if buildings have a life, and a purpose -- and the answer can't be in any doubt.
The questions in your leading paragraph are the ones that communities, and architects, are frequently asked to consider. If members of "that other profession" take an oath to First, Do No Harm, then so must we -- and while waiting to discover what can and should be done with any worthy old structure, we can at least make repairs and undertake the appropriate maintenance. As I understand it, these practices are better known to our European colleagues -- a good thing, as they have in many cases a far older and finer menagerie of buildings to "practice upon."
In the case of Frank Lloyd Wright (when we speak of him in public, we can ease our listeners' impatience by referring to him as Mr Wright after the first mention of his full name,) there are numerous aging structures from his later career which could do with a new coat -- not of paint, which he resisted, but of wood. Just as we re-shingle on a routine basis, so we could (I claim) discard the discolored and disintegrating cypress and redwood boards of the Usonians, every 40 years or so, without disrespecting the structures or their designer. Unfortunately, the conservator mentality attaches the imaginary label "Precious" to every fiber of original building fabric. When I very occasionally hear that some original material from the exterior or interior of a (Wright) building has been removed to safe storage, and replaced on site with a replication, I cheer; what better way to have our cake and eat it too ?
What could be lovelier than fresh and crisp newly-milled wood ? What could be a truer act of respect than to periodically re-start the clock on the weathering surfaces of a beloved building, simultaneously maintaining its health and restoring the appearance that the designer intended ? Are we acting in response to some sort of superstition when we refuse to disturb shabby "original fabric" on historic structures ?
Well, he surely wasted no time ripping apart Taliesin when the mood struck for an "improvement." What architect would say no to any indicated maintenance, including replacement of damaged material ? And, to your question, has an architect ever counseled the destruction of a building when its original purpose was lost, rather than working to devise necessary alteration to fit it for a new use ?
Hi SDR:
You asked about the shop. Sorry it took so long but here is a little snap of our shop space at TWest. In WI things are a bit different, as in our wood shop, and metal shop are separate. I like the separation, it keeps things more open.
I've always liked the idea of an open-air shop -- a deck outside the shop where work can be done in good weather. Perhaps it's only advancing age, but I find I want to work where the daylight is strongest (though of course direct sunlight can be a mixed blessing). Young people seem to be able to work in what I would call "the dark" !
Apr 10, 09 3:55 pm ·
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Adaptive reuse of an historic structure GEN.THOUGHTS.INTEREST
Greetings;
This project is more of an installation of sorts. I call the structure "Furniture" because it seemed like I was building a boxed Ikea product (with better instructions - of course), and because I could dismantle it and install it in another location. The parts fit together in many different configurations with only minor changes needed.
Well, maybe just watch the two flash video's and let me know what you think.
I am most interested in making connections with people/organizations that are also passionate about old building, and how we can (and are) interact with them.
Thanks,
Russell
teaser - pdf
http://www.russellmahoney.com/pdf/Russell_Mahoney_Shelter.pdf
presentation - flash (20 min)
http://www.russellmahoney.com/flash/RDM_midway_pres3.html
assembly (1600x speed) - flash (10 min)
http://www.russellmahoney.com/flash/furn3.html
This is worth a look, I think. I wonder why more student work isn't posted here .
The PDF page is handsome and informative, and the presentation video is marred perhaps only by the insertion of crisp photographs which, nevertheless, lack the perfect timing, and the laser pointer (?), which I'm guessing was present at the live event. Still, it's an engaging and even heart-warming look at the efforts of the fledgling to nest, temporarily, within the parental mammary -- after diligently patching up the sheltering fabric of the Old Cow ?
Because the project as presented is incomplete, perhaps it's best to wait for more photos before judging the result. In the meantime, the assembly video is entertaining and informative; not many artisans are willing to document the onsite erection of untested components for all the world to see. If for this alone Mr Mahoney deserves a hand, no ?
As a long-time proponent of KD and folding "furnitecture," and of course a big Wright fan, this project seems designed to appeal directly to me. I wonder how others will perceive it. Anybody ?
I read the pdf and watched the assembly video. I really enjoy these kit of parts projects. I find it very satisfying to watch each unique piece fit into its own specific spot, though I am also aware that some of your components can be used in varied ways. I appreciate that you aligned the decking with the staircase, visually this is very appealing.
I am curious, what made you place one of the legs inside the staircase as opposed to the extreme point? Placing it at the extreme (bottom of the hexagon when viewed in the assembly video) seems to be the natural location for this member. As it is shown, you have a slight instability in the frame, which is evidenced by the rocking motion as you climb the steps. This is overcome by the weight and shape of the frame, but you haven't really addressed it explicitly.
The front leg - I really wanted that whole front end to cantilever without the help of any leg. I realize given the non bolted nature of the frame would really not give me the moment I needed to suspend that weight. I used a small leg (smaller than the other 4) and "hid" it just out of view. I don't have a shot that shows it specifically, but you can look at this rendering and see what the effect is like.
http://www.russellmahoney.com/images/door_render.jpg
I also considered (and can still execute) removing the stair cage and
having just a clean line across the front - parallel to the entry door.
Here is a mock up I did of the ship stair (today):
http://www.russellmahoney.com/images/stair_mockup.jpg
I was testing two things with this mock: 1- how well a double fillet would do on the stringer side of the .25" plate (apposed to a messy fillet on the foot side of the tread) - It passed that test. 2- the proportions of the treads for a comfortable assent/descent - it passed as well.
Thanks for the replies!
Russell
I'm glad to hear you considered the issues. I realize that your installation isn't permanent and I can only imagine you aren’t allowed to cause any damage to the existing structure, so it is understandable. Were you allowed to operate freely, a classic way to resolve the instability problem would be with some sort of tie back. You’ve got a short cantilever, but it is your main access point, so it basically sees your maximum load. Most likely the easiest way to solve the issue would be to bolt the column bases to the concrete. You could run a quick number, but it is hard to imagine a scenario were the resulting tension force would exceed the yielding of the bolt or the breakout strength of the concrete.
In the actual stair, you are relying on a moment connection, which is one reasonable solution. An alternative would be to create a truss by adding a brace to complete the triangle suggested by the cantilevered stair frame. This would greatly increase the stiffness of the stair, but of course the aesthetic may be unacceptable and is something you’d need to consider. Otherwise, increasing the depth of the tread brace will also increase the moment of inertia and thus the stiffness.
Re. bolting to the concrete: Well let me say everyone is telling me to bolt it to the concrete (even the property manager). There is two reasons I won't do it: 1- how much concrete (depth) actually exists is unknown. Now being at Taliesin for 3 years, I know that there was no standard when it came time to pouring slabs etc... I can only assume and 1" or 2" poured over some earth and crushed sandstone. 2- I am trying not to do any modifications to the existing site (other than repairing the existing fabric).
At this point the movement on the stair cage is minimal. Once the final tension cables are installed, the stair, and the weight of the top deck the movement should be almost null. If I still need more 'umph' on that cantilever I could increase the bolt detail on the fascia, which anchors into 1.5" TnG black locust decking and the steel frame. Currently the bolt detail on the fascia is minimally structural.
I don't think I fully understand what your are suggesting for the stair? Are you speaking of the stair cage, or the ship stair (to the top decks)?
Ok I understand your concern for the site. My point of brining up the stability was really more academic than a specific request. Just encouraging you to consider the issues and giving a little insite into how the issue might be resolved on other projects, which sounds like your professors have also discussed with you. Stability of a structure is an issue that needs to be considered both in the final constructed form and also in the partially constructed state. Please don't take my posts as anything more than commentary and discussion.
My comments about the stair were refereing to the lower stair that you use to climb onto the lower platform from the concrete floor.
Yes keep the comments coming! I like the feedback.
It would be nice If I could put some type of non permanent epoxy on those feet, which could act as an anchor...hmmm.
I'll think about the stair cage truss...but I'm still a little unclear of the detail your describing.
Heh-heh -- "museum wax" is some sort of sticky but harmless substance that is placed under smallish vulnerable objects to prevent damage during seismic events, etc. It's doubtful that this strategy would work at large scale.
I can fully sympathize with the self-imposed "hands off" free-standing requirement. I once built an interior furniture-object superstructure that was attached to an existing cast-iron radiator, and otherwise stabilized by elements that touched opposing walls.
I can't read what's going on at the top; what is the red-colored vertical pipe doing ? Is that an existing element ?
SDR - Yes the Red 3" round pipe, and the red 3" angle are all part of the original structure.
before:
http://www.russellmahoney.com/images/before.jpg
After:
http://www.russellmahoney.com/images/old_new.jpg
In the small gray "signature illustration" of the whole construction there appears to be a perimeter handrail at the top; if this ends up just under the building's two cross beams, perhaps a judicious bit of blocking there will be enough to transfer down-force through the rear leg to the floor, and substitute for the fastening of that leg to the "slab" (I hesitate to call it that if it's an inch thick) ?
SDR - I think I understand. Create a relationship between the buildings existing 8x8s and the slab. Create a member that would be activated once the force is applied to the stair cage (185 pounds ;-). I don't think the relationship would have to be that pronounced...as the 'movement' is minimal-currently.
Surely. On closer inspection, the most direct path might be through either (or both) of the rear leg posts, extended upward as necessary. . .?
Continuing with a critique of the work, I have taken the liberty of copying one of the illustrations from the presentation. I must say my eyebrows tried to disappear within my (receding) hairline when I saw this dog-leg beam
which seems to give new meaning to the term "structural bent" ! But it started me on a quest to map out the alternative possibilities, and to play detective at what the process might have been that led to this choice. I've made some diagrams, in which (A) represents the chosen solution, and (B) is the most obvious, "safe" (if rather unimaginative) alternate.
Why would (B) not do, for Mr Mahoney's purposes -- no fear of deflection, no difficult-to-measure (and resist) combination of bending and torque at the connection between beam and node ? Why invite trouble, in other words ?
One positive attribute of the chosen support point of Mr Mahoney's hexagon frame -- the post, and the connecting node -- is that it neatly occupies what would otherwise be wasted space, between the hex figure and the cylindrical envelope surrounding it. Another advantage is that the post and node do not interrupt the hexagonal surface plane at all.
Also, it seems that one of Mr Mahoney's goals with his structural kit-of-parts is that it be reconfigurable to other uses -- presumably ones of orthogonal, rather than polygonal, plan shapes. To this end, the node is made with receptacles arrayed at 90-degree intervals. The chosen plan (A) permits the use these universal nodes, while (B) would not. So, how about this compromise (C) ?
Well, that solves the node problem, but not the problems mentioned in the previous paragraph. Does that explain why it was rejected ? As a final attempt to solve all the problems (as I see them), I show (D), where the sides of the hex frame are continuous, and are clamped or otherwise fixed to the support node, needing only to be connected at their ends (as in the system presented). Here, the beam is cantilevered from the post (wouldn't Mr Wright be pleased ?) and rigidly fixed at right angles to the vertical.
Incidentally, I am also puzzled by a comment made in passing during the presentation, in which Mr Mahoney says something to the effect that the "hexagonal design" will contribute to the structure and "hold tight" the connections (if I understood correctly). I wonder what attributes of a hexagon-shaped frame would be superior in this regard, over a rectangular one. As far as I know, only a triangle presents such an intrinsic rigidity -- but I may have missed the point.
I will be interested to know if I have followed the designer's thinking with any degree of fidelity -- and I hope to be forgiven for trying to second-guess his methodology.
Drat. Please substitute this
for the second illustration above.
[For ease of reading, here's the whole thing in one piece]:
Continuing with a critique of the work, I have taken the liberty of copying one of the illustrations from the presentation. I must say my eyebrows tried to disappear within my (receding) hairline when I saw this dog-leg beam
which seems to give new meaning to the term "structural bent" ! But it started me on a quest to map out the alternative possibilities, and to play detective at what the process might have been that led to this choice. I've made some diagrams, in which (A) represents the chosen solution, and (B) is the most obvious, "safe" (if rather unimaginative) alternate.
Why would (B) not do, for Mr Mahoney's purposes -- no fear of deflection, no difficult-to-measure (and resist) combination of bending and torque at the connection between beam and node ? Why invite trouble, in other words ?
One positive attribute of the chosen support point of Mr Mahoney's hexagon frame -- the post, and the connecting node -- is that it neatly occupies what would otherwise be wasted space, between the hex figure and the cylindrical envelope surrounding it. Another advantage is that the post and node do not interrupt the hexagonal surface plane at all.
Also, it seems that one of Mr Mahoney's goals with his structural kit-of-parts is that it be reconfigurable to other uses -- presumably ones of orthogonal, rather than polygonal, plan shapes. To this end, the node is made with receptacles arrayed at 90-degree intervals. The chosen plan (A) permits the use these universal nodes, while (B) would not. So, how about this compromise (C) ?
Well, that solves the node problem, but not the problems mentioned in the previous paragraph. Does that explain why it was rejected ? As a final attempt to solve all the problems (as I see them), I show (D), where the sides of the hex frame are continuous, and are clamped or otherwise fixed to the support node, needing only to be connected at their ends (as in the system presented). Here, the beam is cantilevered from the post (wouldn't Mr Wright be pleased ?) and rigidly fixed at right angles to the vertical.
Incidentally, I am also puzzled by a comment made in passing during the presentation, in which Mr Mahoney says something to the effect that the "hexagonal design" will contribute to the structure and "hold tight" the connections (if I understood correctly). I wonder what attributes of a hexagon-shaped frame would be superior in this regard, over a rectangular one. As far as I know, only a triangle presents such an intrinsic rigidity -- but I may have missed the point.
I will be interested to know if I have followed the designer's thinking with any degree of fidelity -- and I hope to be forgiven for trying to second-guess his methodology.
SDR,
that is a great critique, I really like how you break down the process. To tell you the truth, I also had a very similar reaction when i first saw the bent beam but didn't mention it. Thanks for highlighting this issue, and for positing some very effective alternatives.
If I am indeed understanding the diagram correctly, It should be noted that the final solution (D), will introduce some eccentricity of load into the columns(legs) of the frame, due to the beam being offset. This will be most critical at the time of construction before the frame is completed, which brings us back to my previous point about analyzing a structure both in its completed state and in its partially constructed states. Would it not be possible for the beam to continue over the top of the leg, thus eliminating the eccentricity, or will we have strayed too far from the tinker toy origins?
It is possible that the diaphragm created by the decking, if properly connected, will act rigidly, providing stability and stiffness to the frame, but I agree, the hexagonal form is not inherently stable.
Thanks, Synergy. To your point: true -- but that can also be said of (A), can't it ? In all cases, stabilizing the posts (columns) by whatever they are connected to above, would presumably overcome the problem ? (The further up [i.e., the more remote] that connection is, the less force would be placed upon it; a handrail above the second-level platform would presumably provide enough leverage to keep the columns vertical -- to say nothing of an identical second platform itself ?)
The thing that troubles me about the majority of the slip-fit connections in Mr Mahoney's "kit" is that they are not deeper in insertion than the dimension of their cross-section; thus, they seem prone to loosening when bending forces are applied. (This does not seem to be the case with the vertical, cylindrical connections.) Call me "Mr Overkill." Another question I have is whether the system depends upon a complete array of tension cables, some of which are in evidence in the construct. Are these a "fix," applied as and where the need arose, or were they an integral part of the system ?
I note that the complete assembly of the lower platform includes a second steel edge member, this one the full length of a hex side, which is applied over the wood deck boards (which, being laid loose and "dry," will not have the full effect of, say, a plywood diaphram, will they ?). These steel "caps" may be well-fastened to the steel frame below. If so, this effectively answers my original question. . .
Wow - thanks!
This is good stuff.
I'm just back from a little three day camping trip (to that great crack in the earth). I'm looking forward to reading over this more thoroughly so I can be sure to give the appropriate response to your thoughtful/thought provoking critique.
-Russell
Hey great! I was enjoying this discussion before it went a little cold.
SDR,
In answer to your question above, you are completely right, the unattached decking will not provide any rigid diaphragm action. To get rigidity out of this system we would need to attach the decking to the frame, and probably run some steel strap ties between the decking members, perhaps in a Z or X pattern to get something really solid.
More cables ? Even if every board were attached at every point where it met metal, the boards could still slide past each other, defeating the attempt at turning the wood into a structural diaphragm. The boards would have to be glued to each other -- making the system a lot less portable ?
But I'm not sure yet that the lack of rigidity in that plane is significant, here. I'm curious to see what Mr Mahoney thinks of our dissection.
Not cables, but flat strap ties between the decking boards. Along the lines of what this image shows, except in place of the metal studs, we would have our decking, lying in a flat plane. The strap are usually 3" wide material and 16gage thickness I believe, though I believe there are options depending on the specific demand. You are right though, it is intended to provide resistance from the boards sliding past one another.
Hello SDR:
The age old question A vs B vs C vs D...
D works for two reasons:
1 - you are correct with the assumption that the 90degree construction allows for the future use to be an orthogonal option. So C or D would work equally well.
2- What D does that C does not is allow for the maximum sq. footage. The nodes occur almost to the full inside diameter of the existing masonry in the tower. If I were to use option C it would shrink the floor sq. footage. In a 9'3" diameter cylinder I was looking for maximum floor space.
- How do I post pics inside of the post? Do I use HTML?
Russell
The code appears in very pale gray at the bottom of the posting box -- I can't read it. The formula is, add
after it, no spaces. If your image is more than 420 p wide, reduce it by adding "width=420" (no quotes) to the end of your URL, with one space, in front of the [/img] (no space).
What you write is in line with my supposition. How was the Big Hole ? I've never seen it. Are you back in the shop, with the ship stair ? What part of the Taliesin shop is al fresco ? Good equipment ?
Ha -- okay, let's say
The formula is, add {img} in front of your URL, and {/img} after it, no spaces -- but use these brackets []. If your image is more than 420 p wide, reduce it by adding "width=420" (no quotes) to the end of your URL, with one space, in front of the [/img] (no space).
Thus: {img}http://sdrdesign.com/RM1.jpg width=420{/img}
but with []
Synergy:
Regarding the decking. I'm not sure if I understand the strapping technique. I can tell you when I installed the fascia, and bolted the frame, 1.5" TG locust, and the 3/16" steel fascia the whole floor became very rigid.
Here is a detail:
http://www.russellmahoney.com/images/fascia_det.jpg
Can you explain more about strapping? Can this be a possibility to distribute that load from the stair cage?
Thanks
Russell
Synergy:
Regarding the decking. I'm not sure if I understand the strapping technique. I can tell you when I installed the fascia, and bolted the frame, 1.5" TG locust, and the 3/16" steel fascia the whole floor became very rigid.
Here is a detail:
Can you explain more about strapping? Can this be a possibility to distribute that load from the stair cage?
Thanks
Russell
Synergy:
Regarding the decking. I'm not sure if I understand the strapping technique. I can tell you when I installed the fascia, and bolted the frame, 1.5" TG locust, and the 3/16" steel fascia the whole floor became very rigid.
Here is a detail:
Can you explain more about strapping? Can this be a possibility to distribute that load from the stair cage?
Thanks
Russell
Synergy:
Regarding the decking. I'm not sure if I understand the strapping technique. I can tell you when I installed the fascia, and bolted the frame, 1.5" TG locust, and the 3/16" steel fascia the whole floor became very rigid.
Here is a detail:
Can you explain more about strapping? Can this be a possibility to distribute that load from the stair cage?
Thanks
Russell
Russell, when you post images, put in 'width=400' before the final [/img ]. Otherwise it may be too big.
The strapping is designed to create rigidity in the decking for in plane stresses. For example the decking will certainly resist vertical loads from you standing on it, but try to image a heavy stress from a twisting, torsional action on the whole frame, can you imagine how the boards might shift and slide relative to one another? The idea is to get the decking to act as one rigid system (though this isn't always a benefit in every case, it can be a useful quality). You would lay the straps flat, and perpendicular to the decking and attach it to every piece of decking. I would also lay one or two straps diagonally, like the image I posted above (Imagine the image is rotated so that the vertical studs were your decking, and that there was no space between them). The net effect is to create a rigid triangle, which will not deflect in any planar direction. The triangle would be made of two legs of strap and one leg of decking. The exact strap layout would require a little thought since the deck shape is not a simple rectangle, You could attach the straps to the bottom of the decking.
To be honest, this concern is really more academic, as it is very unlikely that your structure would see this kind of load, which would generally result from wind or earthquake. With a properly working rigid diaphragm, if you push on one side or leg of the frame, you will engage the entire structure and all the legs, instead of the single element.
On the other hand, you could ignore any contribution from the decking and return to simply relying on the frame to provide rigidity. In this case you have options of forming closed brace conditions (ie. trusses & triangles) or moment connections. Currently your system is something of a hybrid, but basically relies on the eccentric moment capacity of the members and connections, which is acceptable given the small loads, but would not, generally, be a solution used for larger structures.
While we're waiting for construction to be completed, should I raise the issue of "adaptive reuse of (an) historic structure," the putative subject of the thread ? Russell, did you have questions or comments about this ?
SDR - What is to be done with these historic structures? Should they be restored to their "prime" and be treated like a museum? Should they be adaptively reused for something more appropriate for the time?
- I'm stuck here: I love old building, especially when they have such a rich history, but I also want building to have a function... Does a structure have a soul? What would it be happy doing for the next 100 years?
What would Frank do...
All good questions, for sure. Starting with your own intervention, the combination of tenderly-applied repairs, and a (literally) harmless insertion, seem wholly appropriate. It would tickle me to know that the useful "furniture" you are installing in the milk room might stay in place for years or decades, serving successive members of the ever-evolving Taliesin community -- even though you have evidently designed it to be removable on 24 hours notice.
If man has a soul, then his "trees and rocks" may be more likely to having them too, than the mere furniture of nature. More to the point, we might ask if buildings have a life, and a purpose -- and the answer can't be in any doubt.
The questions in your leading paragraph are the ones that communities, and architects, are frequently asked to consider. If members of "that other profession" take an oath to First, Do No Harm, then so must we -- and while waiting to discover what can and should be done with any worthy old structure, we can at least make repairs and undertake the appropriate maintenance. As I understand it, these practices are better known to our European colleagues -- a good thing, as they have in many cases a far older and finer menagerie of buildings to "practice upon."
In the case of Frank Lloyd Wright (when we speak of him in public, we can ease our listeners' impatience by referring to him as Mr Wright after the first mention of his full name,) there are numerous aging structures from his later career which could do with a new coat -- not of paint, which he resisted, but of wood. Just as we re-shingle on a routine basis, so we could (I claim) discard the discolored and disintegrating cypress and redwood boards of the Usonians, every 40 years or so, without disrespecting the structures or their designer. Unfortunately, the conservator mentality attaches the imaginary label "Precious" to every fiber of original building fabric. When I very occasionally hear that some original material from the exterior or interior of a (Wright) building has been removed to safe storage, and replaced on site with a replication, I cheer; what better way to have our cake and eat it too ?
What could be lovelier than fresh and crisp newly-milled wood ? What could be a truer act of respect than to periodically re-start the clock on the weathering surfaces of a beloved building, simultaneously maintaining its health and restoring the appearance that the designer intended ? Are we acting in response to some sort of superstition when we refuse to disturb shabby "original fabric" on historic structures ?
What would Frank do ?
Well, he surely wasted no time ripping apart Taliesin when the mood struck for an "improvement." What architect would say no to any indicated maintenance, including replacement of damaged material ? And, to your question, has an architect ever counseled the destruction of a building when its original purpose was lost, rather than working to devise necessary alteration to fit it for a new use ?
Hi SDR:
You asked about the shop. Sorry it took so long but here is a little snap of our shop space at TWest. In WI things are a bit different, as in our wood shop, and metal shop are separate. I like the separation, it keeps things more open.
I've always liked the idea of an open-air shop -- a deck outside the shop where work can be done in good weather. Perhaps it's only advancing age, but I find I want to work where the daylight is strongest (though of course direct sunlight can be a mixed blessing). Young people seem to be able to work in what I would call "the dark" !
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