I noticed an echo free dome after completing cement work below. This ferrocement dome has proven echo free, ever since. Musically inclined visitors agree that no echoes are heard. Coffer styled, fire proof structure integrates framing, sheathing, and scaffolding. Coffers inherently add structural efficiency, providing more strength through "the framing effect", built in with the sheathing or skin. Coffers also make possible "additive construction". This is the construction method used by 3d printing, acclaimed to revolutionize the world. I beg to differ just a little, by preferring computer aided inspection, to build full structures.
My purpose for building this was to experiment with "fractally curved surfaces". Integrate geometry, structure and composites, or ferrocement. (This favours thin walled, tensile and cementitious composites). The echo free ambiance was a very rewarding result. Stone hard interiors normally bounce echoes which are not pleasant. Integration of sound dampening with efficient structure, in spacious, cementitious interiors, should be realized as a desirable advantage. This building plan began around the year 2000. Since that time, the building simply houses my tool shop, a storage loft and greenhouse. Architectural software tools have improved too. Here is a 2012 prototype structural, variable geometry system, (developed in formZ software):
Architectural software is gradually enabling this type of rigourous structural modeling. Variable sized coffers allow efficient building of free flowing structural shapes. Coffers are arguably more efficient than flat, thick skinned structure, but English dictionaries may fail to note that important point. This page shows immediately available forming systems, built entirely single handily. Imagine what a team could further develop!
My year 2000 geometry tools, (example below) was very limited. Better coffer-geometry tools are in hand today.
My own expectation is that a largely anechoic auditorium could be built using a hard surfaced interior. To achieve echo free ambience at a lower cost, (for large, clear-span structures). There seem to be some structural and budgetary advantages. The costs of fire safe, soundproofing usually requires additional skilled trades and considerable extra material costs. What are the desirable acoustical effects for music halls? Do we want resonance and polyphony? Can structure enhance music played within? Can we experiment with such effects by altering coffer shapes and sizes? Many questions can follow. Contact me for an interesting discussions. I can skype. but let us start with email first.
As a creative, i work on a shoe string budget, but love to experiment with structure. My additive-construction-method, for ferro cement was used here. I always look for minimal expense approaches, in construction. Construction-quality for me is dependent primarily on the bigger picture one's situation in life. I do favor polished finishes but cannot afford this feature. My work is crude so far, but it discovers new assets for advancing the additive method of cementitious structures. Note that my cheap scaffolding uses the dome itself, (in picture below).
Typical dome projects rely upon reinforcement in the skin alone. This reliance results in less efficient use of material. Typical domes are typically thick, solid shells applied with bigger budgets. Those same budgets could go further, if indeed coffers are more efficient. Also the ecological purpose of doing more with less should be compared. Additive coffers provide framing and sheathing in one basic unit. The additive building approach is also more affordable to smaller, independent builders.
The anechoic aspect was noticed around completion of the ferro cement work in the summer of 2006. Above picture: The last few coffers (or bee cells) are snuggled in, (molded into place). Photo below taken from ground floor viewing up through central opening in the second floor.
The second floor (below the dome ceiling) has integrated joists which intersect at 60º angles. (Or running in 3 direction). I continue to wonder about structure. Another aspect is the notion of "fractal vaults". Or coffers arranged into a larger vault or dome. Following are some 3d models to show this.
My search always continues for structural efficiency. Below follows yet further structural concepts which more directly incorporate framing and truss work. It seemed to me that "channel beams" in the form of half cylinders (or arched channel, or half split tubes) should easily 'union' together. (Integrated structural components instead of woven components). Here are much earlier examples of my framing exploration. The next picture shows integrated channel structure in a dome.
Efficient structure is expected in these examples. In this picture above and picture below, in both pictures, the concave surfaces face indoors. In this example (picture above and picture below, both pictures:This same 3d model uses many individual channels by crossing paths. Two of the individual channels are drawn below:
The next geometric model below shows these same tubes inverted. So that the the concave surfaces face outside! What use could this serve? My expectation is that it will serve as the best possible "green roof" function. Soil or equivalent can be held on sloped surfaces, (like any, well-made structural roof system).
The version above represents many planter indentations upon a surface of a concavely subdivided dome. Next concave and convex are compared.
Many structural subdivisions are conceivable. In all cases presented here, the interior surface does interfere sound waves which should reduce echoes. Which arrangements can work most favorably? Next is a simpler adaptation of soccer ball sections arranged in ring clusters. It can be formed and reinforced efficiently with ferrocement, concrete or tomorrow's composite material.
Miserly building experiments with ferrocement structures convince me that 'ball' or 'inner-tube' form work are the most cost savings methods, (for larger, clear-span, cementitious structures). I've 3d modeled a variety of clear span structures.
Arched Purlin Truss!
I would love the opportunity to study large, clear-span structural models, suitable for an auditorium. The picture below shows a proposed cross section for a large auditorium. 3d models of this extent take much more time to develop. (The essence of coffers is emphasized. Full truss-like boundaries are intended, but not shown).
New pages will eventually be added as modeling time permits. High-resolution pictures are available, ask me. Below was an early effort to model coffer divisions with arched truss works. (Actually, the truss sections are meant to form a larger dome structure, but fitting "fractal vaults" take much more computer effort and human time.
The effect of stalactites 'dripping' from ceiling is a natural outcome. I love finding natural results and a structural metaphor as well. This outcome relates to my earlier study. A re- curve cable arch night serve more efficiently, in case echo-free acoustics are sufficient with coffers alone3. It is all an exploration of using steel with vaults and with coffers, to reinforce structures. Or, of using strong tensile members inside composite structures. In any event, stalactites predate and also appear very much like the classical anechoic structures used in experimental science. I wonder if integrating domed-coffers along with stalactites inside a huge vaulted ceiling will enhance polyphony. Let me know your thoughts.
Much more can be said about observations while using my dome building shown above. I never expected to 'finish' my dome to highly polished standards. Only the conceptual prototyping was expected, to a large extent. My low income and under-employment further explains the very rough finish in my work. I can't afford much effort or money to sanitize my prototypes. Creatives usually cannot afford building all of their own visions. You can see what other ambitions were realized on a shoe string, click here. Or why not avail from creative services? Consider consulting with me online. Buy consulting time for your own dreams, while supporting this kind of progressive ability. My model-consultation might help convey your own dreams to your people, your builders, engineers and architects. I even offer hard labor to speed up creative building projects (in stone, metal, glazing and varied green skills). My rates are very reasonable, click here.
My dome design intended to represent a tree grove. The coffers were meant to emulate leaves. Some earlier pages show the struggling construction phase. Hired help amounted to a few percent of the labor. I did everything else alone. See linked pages here. There are some earlier pages documenting my builder-progress, while building this prototype.
Description of my project quandaries, due to creativity unleashed, (suffering for art). Admittedly, my haste made some waste . I reveal my learning experiences openly, without glossing over them. We are not trying sell poor qualities, but rather show the intuitive evolution of consciousness which inspires the process of creativity and productivity; all done on very low budgets while juggling all difficulties of human life.
The sunny side of this structure incorporates a greenhouse glazing study. I say study meaning living with temporary glazing and raw, unfinished surfaces. All of which can evolve one's consciousness, if one's purposes remain positive and honest. Consciousness evolution opens doors to insights if we work purposely, through constraints we find on our planet. Work will continue and provide it's own direction, over time. I'm grateful for arriving where i am.
One of my worse goofs was my negligence under duress- My failure to strictly follow my intended dome-slope/curvature, during my coffer installation. My circumstances were very crude- I was disappointed that my computer aided inspection implementation was too crude to use on these coffers. My manual-centering for the dome was hampered by obstacles of scaffolding and some impatience as well. Outside income-bearing-jobs distracted my focus. Better building-systems were too luxurious for me on a very low budget. The main emphasis was structural exploration (with practical uses). Each day demanded visible 'progress'. "Keep that hand on the plow." Besides that, these were the years when totalitarian whistle blowing was proliferating on the internet- I multi tasked building work with listening to the world-hierarchical issues, through peer-reviewed mp3 radio shows, (of hard evidence which cannot be ignored).
It was not until the 5th course or row of coffers that the curvature implications startled me: The implication that my earlier coffers should have sloped more inwards. It was too late. So, my solution was to sharply adjust the angle in the 5th course. This abrupt 'adjustment' is seen in morning sunlight. Where the abrupt change of slope casts sharp shadow contrasts, instead of a more gradual dome shading gradient. I added some collar-tie-reinforcement inside. (At least a little extra head room was gained from the fault. A bit of lightweight cement on top could improve the look, but many other priorities persist).
While the clear span was proven, standing unsupported for some years... Installation of cross ties were added as extra reinforcement and also as support for storage (as in an attic).
Winter of 2011-2012, on the ground floor, my steel workshop is finally getting somewhat organized:
This, after 3 decades of keeping these tools mostly outdoors through hard winters! Such has life been for me.
I was always more interested in integration of art, science and philosophy as one occupation in-situ. Which naturally is a no-seller in a materialist humanity, so caught up in self defeat, as humanity is. The imagery of "a ship wrecked but romantic planet" managed to sustain me. This provided more time to focus on mind and spirit as well.
End Of My Dome Article (Last Update February 2015).
I ponder some aspects of human history of building, as follows.
Vault structures have traditionally been formed with stone or brick materials, without use of tensile or steel reinforcements. Humans typically deforest a whole region and then revert to masonry. Gravity firmly held the stones or bricks together. Introduction of steel-reinforced structures has forgotten the advantages of vaults and fractal structure. Apparently, steel and tensile materials can provide advantages in building curves, domes vaults. I'm all for wood, bamboo and other organics too, but humans are too rushed for natural, evolutive growth. Here is where building structures needs to integrate inherent responsibilities. We humans are too impatient to study the feasibility of infinite market growth, at the risk of human extinction. Blind profiteering ignores or hides consequences of causes and effects. Natural laws are ignored. I admit to dwelling on this point , at the risk of loosing clients who believe in infinite mechanistic growth. Can a given enterprise sustain 7 human generations? I say humans need to evolve or build consciousness before ignoring outcomes. I focussed on material conservation, even struggling with salvaged wastes, all to widen my perspectives and tame my ego. I doubted that the sterile styles of expanding markets should be supported or emulated. I doubt the hierarchy of humanity knows what it is doing to it's future. Posterity will abhor our current market trends. Perhaps this hierarchy is trading humanity away, trading the biosphere as well.... All in hopes of replacing natural humanity with a race of robots or cyborgs. I differ from that by saying humanity needs to discover true, natural harmony with all natural species and thereby evolve human consciousness, as a priority. Let mechanized materialism take it's natural fall, because it is ruining a good planet called earth. The world condition is so bad that we humans might as well not prioritize materialism and the madness of infinite- materialistic- growth.
Conceptual artist is repressed?