Thursday, January 24, 2013

Masonry design and nuclear bombs

I have always been intrigued by the effort of the Manhattan Project to develop the world’s first nuclear bomb.  In particular, I have been fascinated with the geometry used by the scientists to achieve critical mass.  Oddly enough, this effort may be seen as one of the earliest uses of “geodesic” masonry.

For this nuclear fission bomb to work, a precisely defined shockwave occurs which squeezes together the radioactive material at the center of the explosion.  Radioactive material is surrounded by a series of explosive charges (called ‘lenses’) which all go off at the same time; the high energy shock wave of the surrounding high-explosive charges squish the radioactive material into itself so much that it reaches critical mass and a nuclear explosion results.

The shaped explosive charges used in the “Fat Boy” bomb built by the Manhattan Project were configured as a truncated icosahedron, like a soccer ball (pentagons and hexagons).  It was critical that the shapes were located precisely around their nuclear target, for a shock wave to be evenly surrounding the target nuclear material, and so that a focused delivery occurred simultaneously from all around the target.

I could write more about this interesting subject, but I fear that I will end up on some top-secret list or will be sought out by terrorists for my cunning expertise in nuclear weapons design.  I’m just kidding guys!  I am not an expert in nuclear weapons design.  Really.  Truly.

I wonder if the scientists assembling this weapon thought of themselves as masons?  Probably not!

Saturday, January 19, 2013

Topological interlocking structures

I recently came across an interesting paper done by a team of physicists and mathematicians titled The Concept of Topological Interlocking in Engineering  by AV Dyskin, Y Estrin, E. Pasternak, HC Khor andAJ Kanel-Belov of the Department of Civil Resource Engineering, the University of Western Australia, Australia; Institut fur Werkstoffkunde und Werkstofftechnik, Technische UniversitatClausthatl, Germany; and Unversity of Bremen, Germany (Materials Science and Engineering, Volume 31, Issue 6,August 12, 2011, pp.1189-1194).

The work described in this paper by this team is very similar to some of the work I have been conducting over the past 20 years or so.  First, they identify their inspiration as occurring in the biology of nature, as I have also done (see “Nature’s Masons” on this blog). 

Secondly, they describe how a structure assembled from their interlocking units is toughened, as it is resistant to crack propagation between adjacent interlocking units (as I have also described several times on this blog, e.g. “Harder, stronger, stiffer, tougher”). 

Third, they provide a rounded edge to their interlocking shapes, so as not to focus stress, as I have also described on this blog (see “The art of limits (and the limits of art”).

The authors point to the failure of thermal tiles on thespace shuttle Columbia as one example of how their concept of “topological interlocking” can be advantageous by providing a toughened structure held together by geometry alone; which is at the very heart of my own work.  The authors' system is comprised of parts interlocked with the concave features of one block interlocking with convex parts of another block, and vice-versa.  This is precisely how my dual-inverse mirror plane (dimp) arrangement works also. 

They assembled flat (planar) sections of structure using various polyhedral arrangements and tested these for strength.  They found that the resulting planar configurations could withstand significant stress tests, and furthermore that loss of one or more interlocking block did not necessarily result in failure of the structure.  Again, this is what I have been saying about my own system for years.

The work of this team is very interesting, and validates and substantiates much of what I have been saying for years.  Their system does lack a few of the advantages to be found in the designs I have developed.  First, their topological interlocking units create an undercut, or draft, or negative angle which cannot be readily released from a simple two-piece mold (unlike my system).  Secondly, their system is not capable of conjugate shearing in the same ease of manner which triangular shapes inherently allow.  Third, they build flat planar structures, and their system does not allow for a radial (spherical and cylindrical) structure as readily, as easily and as strongly as my system does (my system can also do flat planar structures).

I was delighted to see this work and realize that other teams of engineers share the same insight into the advantages inherent in a system comprised of interlocking unit shapes.

Thursday, January 3, 2013

The lack of innovation in masonry

Masonry has existed as a form of construction for thousands of years.  Its lineage predates recorded history, and is steeped in tradition and long-established practice.  While other fields of human endeavor have undergone fundamental changes and have evolved over time, the basic practice of masonry has not really changed much over thousands of years.  A mason from 1,000 BC would recognize today’s masonry techniques as being very much akin to what was practiced over 3,000 years ago.

Why has masonry remained fundamentally unchanged for so long?  What factors have contributed to masonry remaining essentially static over such a long period of human history amidst dramatic changes and new developments in virtually all other fields of human creativity?
This is a curious question which is difficult to answer.  Others have addressed this question, and their findings are worth looking at.  An article from 1989 by Clayford T. Grimm asks this question, and is appropriately titled “Why are there so few innovations in masonry?”  Mr. Grimm posed this question to a steering committee for a workshop on masonry research sponsored by the National Science Foundation (USA).   Committee members included the Masonry Institute of America, the National Concrete Masonry Association, and Clemson University faculty members.  Their findings are noteworthy, and are listed as follows:

1.  U.S. tort law.

2.  The bureaucratic building code process.

3.  The unfunded process of writing consensus standards.

4.  Industry fragmentation.  “Economic pressures for fast construction time leave little time for the learning curve required by new ideas.  The construction industry mind-set supports the status quo.”

5.  Research fragmentation.  No government agency is funded to research masonry problems.  Given today’s fiscal challenges of government, there is not likely to be any such agency in the foreseeable future.

6.  Educators teach what they know and few of them know much about masonry.

7.  Designers are reluctant to use masonry structurally because of poor jobsite quality control.

8.  Academicians who dream up new names for old ideas and make a career out of it.

9.  Designers who don’t care about mason productivity.

10.  Lack of financial incentive.  “Why should a builder build a $50,000 house for a low-income family when for about the same effort he can build a $150,000 house and make a lot more money?”

[This article was originally published by The Masonry Society, and presented at a workshop sponsored by the National Science Foundation in Washington DC, August 28-30, 1988]
While the points made in the article as discussed above are important and noteworthy, it seems that there is still more to the question of why masonry remains essentially unchanged and is resistant to innovation.

One seemingly obvious factor points to the long history of masonry, across geography and among different societies, countries and cultures.  Because masonry has been practiced for so long, and has been developed as an art for so long, it has already been rather fully developed.  As such, there appears to be little room for improvement or innovation.  This may seem trivial or obvious, yet I believe it is worth stating.
The notion that masonry has been fully developed over several thousand years and cannot be substantially improved upon is strengthened by the contemporary practice of masonry research.  Contemporary masonry research is primarily involved with the analysis of Romanesque, gothic, medieval and other ancient masonry structures.  Most notable masonry engineers have spent their careers looking back at some of the great architecture of humanity’s past accomplishments to gain a more complete understanding of the engineering involved.  For example, Jacques Heyman has done extensive analysis of masonry architecture in several books such as The Stone Skeleton (Structural Engineering of Masonry Architecture)  Cambridge University Press, 1995.  Mr. Heyman has a long list of such publications, each of which looks at explaining the engineering involved in old masonry structures.  Current masonry engineering work has a real focus on the past.

Another factor in explaining the lack of innovation brought to masonry is the mistaken notion that old ideas re-discovered and re-introduced are in fact new.  One example of this is the thin-shelled catalan arches originally developed in Europe (especially Valencia, Spain) in the 14th century.  This type of masonry was re-introduced as a “new” type of construction in the US by Raphael Guastavino in the 19th century in the US.  More recently, similar work is being done by people at Massachusetts Institute of Technology; it is also being touted as “new” but it remains essentially unchanged since the 14th century.  MIT’s work on catalan arches is essentially derivative of much earlier work.  This phenomenon is close to #8 on the list which began this blog, as described by C.T. Grimm.
Finally, there is a curious and fascinating observation made by Frank J. Sulloway in his watershed book Born to Rebel  (Vintage Books, 1997; New York Times “notable book of the year”).  “Sulloway's most important finding is that eldest children identify with parents and authority, and support for the status quo, whereas younger children rebel against it. Drawing on the work of Darwin and the new science of evolutionary psychology, he transforms our understanding of personality development and its origins in the family.”  Sulloway describes how virtually all truly innovative ideas are the product of a last-born or later-born child, and explains this as a means to gain their parent’s attention.  It is essentially a Darwinian survival mechanism.  Conversely, first-borns are much more conservative and tend to end up in positions of power and authority.  These factors combine to create a scenario wherein a last-born innovator is presenting an innovative idea to a CEO or president or other authority who is typically a first-born conservative thinker.  While this idea may appear esoteric and irrelevant at first, I believe it has real merit.

Where do I see myself and my innovations in masonry?  I am a last-born child (youngest of four).   Are my ideas real innovations?  I believe they are; others do too.  I have had several US patents awarded for my ideas.  They were also identified as a “Cutting Edge Technology” by the American Concrete Institute.  Finally, there is no other masonry system like the one which I have developed.  How can this be?  I do not imagine myself some sort of unique genius.  I think I have been fortunate to have investigated ground which others have not.  Part of this is due to the fact that geodesic geometry was most recently developed by R. Buckminster Fuller (first developed by the ancient Greeks).  It was my good fortune that Fuller assigned great value to how much a building weighed (as I have discussed several times earlier on this blog).  This aspect of Fuller’s thinking was closely held by his followers, which meant that masonry was never considered as a suitable construction material; it was always thought to be too heavy.  His bias against massive material such as masonry left a niche for me to investigate and develop as I have.  My experience as a ceramic artist and mold maker provided me with the insight and awareness of mold releases, undercuts and interlocking features.  My education in geology and fault mechanisms opened my eyes to conjugate shearing.  Through focus and hard work I brought these things together in an innovative masonry design.
Is there room for real innovation in masonry today?  I think there is!