Lightweight Concrete by MIT Architecture

EXHIBITION DESIGN AND CURATION TIMOTHY COOKE AND JOHN FERNÁNDEZ

EXHIBITION TEAM TIMOTHY COOKE JOHN FERNÁNDEZ DAVID COSTANZA NICHOLAS SOANE

EXHIBITION DOCUMENTATION TIMOTHY COOKE JUDITH M. DANIELS, SA+P THE KELLER GALLERY AT MIT ARCHITECTURE ROOM 7-408, MIT 77 MASSACHUSETTS AVENUE CAMBRIDGE, MA 02139-2307

SERIES EDITOR

SARAH M. HIRSCHMAN

PUBLISHER

SA+P PRESS CAMBRIDGE, MA 2013

PRINTER

PURITAN PRESS HOLLIS, NH

CONTACT SA+P PRESS ROOM 7-337, MIT 77 MASSACHUSETTS AVENUE CAMBRIDGE, MA 02139-2307

CONTENTS BETWEEN DISCIPLINES; BUILDING MATERIALS RESEARCH TIMOTHY COOKE

EXHIBITION IMAGES

THOUGHT AND THING JOHN E. FERNÁNDEZ

LIGHTWEIGHT CONCRETE WAS PRESENTED IN THE KELLER GALLERY AT MIT ARCHITECTURE IN OCTOBER 2011.

BETWEEN DISCIPLINES

BUILDING MATERIALS RESEARCH TIMOTHY COOKE This research project is about developing better building materials: materials that are more sophisticated, have a reduced environmental impact, and can be used to create more efficient and beautiful buildings. More specifically, the research aims to create a better concrete for use in building construction, asking, Can we imagine a concrete that can do everything we might want it to do? What might that concrete look like? This question has manifested as a research program

Timothy Cooke holds a Master of Science in Architecture Studies from MIT (2012) and a Bachelor of Architecture from the University of Oregon (2007). His ongoing research is concentrated on developing variable density concrete. He teaches at Northeastern University and maintains a dynamic object-making workshop at Artisan’s Asylum, a nonprofit community studio in Somerville, Massachusetts.

focused on developing robust, economical and practical casting methods for producing controlled density compositions within aerated concrete building elements. The primary objective of the project is to develop the ability to “tune” the density of concrete, opening up the possibility for better strength-toweight ratios, the inclusion of thermal insulating capacity, lowered embodied energy, reduced material consumption, and enhanced durability and surface quality. Through the exploration and testing of novel ways of producing concrete, the project has resulted in the invention of a new variable density concrete. Parallel to this primary research question is a secondary desire to conduct a self-reflective research program. Here, the intent is to focus on the process itself and draw conclusions about the relative merit of the various kinds of work conducted for the project. In many ways, the research occupies a space between the disciplines¬ of architecture, engineering, and material science. There are inherent benefits and drawbacks to working in this in-between space. Throughout the project, the ambition has been to understand how best to integrate these diverse fields in such a way as to serve the very pressing and real need for better and

more intelligent utilization of building materials. As engineers, architects, scientists, and even artists, we must have these high-level discussions if we are to make any significant progress in this field. My hope is that this research project can serve as an example of the value of such interdisciplinary work. The prototypes and material samples produced over the course of this research project were displayed at the Keller Gallery during the month of October 2011. This document is intended to function as a brief introduction to the work displayed at the gallery and serve as a record of the exhibition.

BACKGROUND One might ask, why focus materials research on concrete? The simplest answer is that concrete is the most abundant of all manufactured solid materials produced today. We use so much concrete that it is second only to water as the substance most extensively used by humans on the planet today. The manufacture of Portland cement, one of the main constituent components of concrete, is an energy intensive process and significantly contributes to greenhouse gas emissions. In fact, Portland cement production alone, depending on the source one cites, has been calculated to account for up to 8% of all anthropogenic CO2 emissions. Natural (dominated by wood) 9%

Metals 6%

In light of this huge environmental impact as well as concreteâ&#x20AC;&#x2122;s ubiquity as a construction material, Polymers 1%

there is great opportunity for reducing the impact our built infrastructure has on the environment through the development of more environmentally friendly concrete. There are two ways to approach this. First, we can reduce the embodied energy and environmental impact of the concrete we use in our built environment. And second, we can develop concrete products that minimize the quantity of raw materials needed for a

Ceramics (dominated by concrete) 84%

given function. We might call this second approach

dematerialization. This work has mainly been focused on achieving dematerialization through the cellularization of a solid material. Cellular solids are identified by a particularly organized distribution of material that results in discretized compartments delineated by thin

Material usage measured by weight (data source: Ashby 2009)

walls or separated by columnar struts. These pores, generally occurring at the micro scale, have dramatic

relative density:

1.0

0.3

solid with isolated pores

0.13

cellular solid

ramifications in terms of the material properties of the cellularized solid. Most importantly, strength and thermal conductance are reduced as the porosity of the material increases. In contrast, by changing the overall shape of a material, a material can be distributed at the macro scale in order to better utilize it. Itâ&#x20AC;&#x2122;s possible to illustrate this way of distributing material by thinking about the stiffness of materials as it relates to shape. For example, by changing the

A gradation of porosity, with the division between a solid with isolated pores and a cellular solid indicated

orientation of a rectangular beam with the same cross-sectional area, one can drastically alter its ability to resist bending. This is called the shape factor: if one can distribute more material farther from the neutral axis of a beam, it will be better able to resist bending. This is why we have I-beams. And yet it is possible to enhance the potential efficiency and sophistication of a structural component beyond what an I-beam provides, by considering material distribution at the micro-scale in combination with overall shape. If we can determine not only the shape of a material, but also the internal distribution

The effect of orientation on a rectangular beam in bending

of that material within the given shape, we can imagine much more sophisticated materials. One sees this everywhere in the natural world. For example, many bones display intricate internal structures that are optimized to resist the forces imposed on the bone. I-beams and sandwich panel structures in buildings allow us to better utilize materials, but we have few materials whose internal composition varies with the level of sophistication seen in nature.

A cross-section of a human tibia. Like many bones, the outer shell is an almost fully dense compact bone that encloses a core of porous cellular, cancellous, or trabecular bone. (reproduced by permission: Lorna Gibson)

I approached this problem by taking a step back and looking at how we have traditionally processed materials for human consumption and use. For example, the process of forging metals not only allows the manipulation of the material into the desired shape, but also reorganizes the crystalline microstructure of the material, making it stronger. This type of process - where a material is transformed at multiple scales producing multiple effects - I loosely call material manipulation. Throughout history we have demonstrated a prodigious ability to manipulate materials to suit our needs. From ceramic pottery to the felting of animal fibers, humans have developed ways of transforming raw materials into useful products. Another way we transform materials is through assembly. For example, we can assemble materials with different properties to create desired internal compositions. This is the concept

underlying the composite materials that have proliferated in the last century and become commonly

altered geometry

utilized throughout the many industries. But despite the power of composites, they donâ&#x20AC;&#x2122;t tend to go beyond the basic function of combining individual elements that are assembled to achieve a desired outcome. Walls, for example, consist of discreet elements that address individual performance requirements (this was one of the main projects of modern architecture). In the work presented here, I am more interested in

combined

the idea of material manipulation to achieve a desired outcome than the assembly of materials to create a final product.

altered internal composition Two ways to think about distributing material

To this end, the experimental work has centered on the exploration of techniques for affecting the material as it is being formed. I have explored both passive and active manipulations. These explorations began by looking at phenomena such as the effect of gravity on the material as it was being formed. But the bulk of the work has focused on how to exploit the interaction between a formwork and the material being formed to produce a cellular concrete with an integral density variation. Traditional cellular concrete is a precast lightweight product that has been used for over a century as a building material. It is typically used in block form in much the same manner as one would use

material assembly

a concrete masonry unit. Its primary advantage is its low density due to its cellular structure,

which in turn gives it insulating capacity. But as mentioned before, in addition to thermal resistance, the cellularization of a solid material reduces its strength. In addition, cellular concrete is commonly cured in high temperature and pressure autoclaves, which increases its strength and stability, but also significantly increases its embodied energy. The pores in cellular concrete are usually produced

material manipulation

through the use of a very small amount of a chemical admixture that reacts with the alkaline environment of the wet mixture, producing gas bubbles. The material expands much like rising bread. This convenient

Assembly of material versus manipulation of material to achieve a desired internal composition

analogy can be extended to the subsequent high temperature curing process: after rising, the bread needs to be baked in an oven. The high temperature autoclaving changes the chemistry of the calcium silicate hydrates of the cement, producing a much stronger and more stable form of hydrated cement. Aerated cellular concrete can also be cured at room temperature, but strength is reduced and drying shrinkage is a concern. I chose to forgo autoclaving because one of the goals of the research is to reduce the embodied energy of the material. Instead, I am attempting to achieve desired strength through the inclusion of denser material where it is most needed within a specific cast element. (Generally, it has been shown that the compressive strength of concrete increases exponentially as the density of the material increases.)

EXPERIMENTAL RESULTS Over the course of a year, I performed a wide-ranging series of experiments. The experimental work resulted in the development of a number of methods for creating density gradients in aerated concrete. Through image analysis of crosssectional slices of samples, it is possible to plot relative density along the length of a sample. The following images and plots document the density gradations I was able to produce using the various methods developed during the course of the research project. The primary technique investigated employed â&#x20AC;&#x153;active formworks,â&#x20AC;? or formworks that did more than solely dictate the overall shape of the cast element. By utilizing the interaction between the formwork and the aerating concrete during the window of time in which it rises, I was able to locally inhibit the chemical aeration of the concrete, thereby creating gradations of decreasing density as one moves farther from the surface of a cast element. These density gradients were exciting, but only provided a proof of concept. To actually test the increase in efficiency one might be able to achieve through the inclusion of strategic density variation, I produced gradient density beam prototypes. These beam prototypes were simple in design, exhibiting continuous variation along their vertical axis that approximated the variation in compressive and tensile stresses found in a simple beam in bending. In this way, the beam could be optimized to resist bending while minimizing weight and material usage. Strength testing of these prototypes showed that a simple design like this could generate a material savings of about 25 percent over a uniformly dense beam of the same geometry without reducing its strength.

APPLICATION WITHIN THE BUILDING INDUSTRY The variable density concrete invented during the course of this research project has the potential to be deployed in beams, columns, blocks and panelized systems. On the following pages are examples of what some of these configurations might

Ratio of solid fraction to total volume (Vs/Vtotal )

1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0

27.5

Distance (cm)

Ratio of solid fraction to total volume (Vs/Vtotal )

1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0

10 Distance (cm)

20.7

Ratio of solid fraction to total volume (Vs/Vtotal )

1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0

11.8

Distance (cm)

Ratio of solid fraction to total volume (Vs/Vtotal )

1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0

15 Distance (cm)

24.3

look like in their most basic form. I did not investigate tensile reinforcing for this project, but the intent is that tensile reinforcement regimes would be integrated into these gradient density morphologies. It should also be acknowledged that the methods Iâ&#x20AC;&#x2122;ve developed for densifying aerated cellular concrete only work at certain scales. In general, densification occurs at up to about 6 inches into any cast. In a cast with a 12-inch depth, for example, one would see continuous variation, but in a cast with a 20-inch depth, variation could only occur in the first 6 inches from the surface of the cast element. The goal of this project has been to imagine a more sophisticated, variable-density cellular concrete. Such concrete has the potential to achieve higher strength-toweight ratios, thus reducing the amount of material needed for a given function. By cellularizing concrete, one can also introduce beneficial thermal properties, which addresses the energy used in the operation of our buildings. By utilizing room temperature curing and low embodied energy Portland cement replacements such as Fly ash, one can start to imagine a concrete that vastly improves on existing technology.

Block types

Beam types cross-sectional composition

one face

two faces (opposite) two faces (adjacent)

three faces (config. 1)

two faces (opposite)

three faces (config. 2)

two faces (adjacent)

four faces

Column types

plan view

three faces

Slab

radial gradient

Panel

one face

two faces

radial gradient

THOUGHT AND THING JOHN E. FERNĂ NDEZ John E. Fernandez is Associate Professor of Building Technology, Department of Architecture, MIT and CoDirector, International Design Center.

MATERIAL DESIGNS Among the most intimate and least understood steps in the design process is the transformation of thought into physical artifact; from intention to material realization, from thought to thing. While the production of a physical artifact often serves to substantiate this transition, it may often do so without revealing the mechanism of that process. Design often engenders quickly arriving at the production of a physical thing of wood, metal or ceramic, or other material worked into a specific geometric configuration by way of casting, cutting, joining, 3D printing or other process. What results is the sudden meeting of the antecedent design thinking with the physical artifact of specific material and geometric attributes. Studies of technologically-intensive design have attempted to comprehensively describe this transformation within the broad spectrum of diverse design activities. The codification of design processes has enlisted a broad range of disciplines from cognitive, behavioral and social sciences to the â&#x20AC;&#x2DC;hardâ&#x20AC;&#x2122; sciences and engineering. Also, there is a substantial literature produced by researchers and thinkers examining design from a scientific perspective. This work has focused much of its attention on engineering practice and education and is known as design science research (Hevner 2004) (Horvath 2004) (Dym 2005) (Magee 2013). This kind of attention has prompted the development of a variety of methodologies using both quantitative and qualitative metrics supported by physical and digital tools meant to improve the practice and results of technically-intensive design. In the process of transforming thought into thing, functional mapping, performance simulation of many kinds, prototype design and testing and material selection (to name just a few methods) are changing the ways in which design is carried out. Today, the codification of the design process and the development of supportive strategies and tools has led to an almost seamless transition between design intention and the physical attributes and performance of the resulting artifact. However, in several diverse design cultures the relationship between thought and thing remains stubbornly and sometimes profoundly shrouded in a veil that belies a definitive mechanistic mapping. Architectural design is one of these processes. As a result, the following questions are not easy to answer. When does design intent achieve physical reality; is it at the very instant of sketching or modeling or does it only come when physical modeling occurs? Does it happen sooner, at the initiation of an organized verbal articulation, or even earlier than that? Is it physical at

the earliest emergence of intent? Can design thinking happen without physical, material intent? It is possible to argue that the simple notion of a transition between thought and thing is essentially problematic and not useful. If we accept that design is always conducted within a physical context; that we, as physical beings cannot reduce cognition to essentially non-physical mathematical and computational calculation as antecedent to intention, then a fundamental prerequisite for design thinking is the experiential ether of the physical world. Therefore, all design intention is inescapably material; there is no transition because all thought is conducted in the physical world. We think and learn as we exist, move through and interact with the physical world. As the results of research in artificial intelligence has shown for some time now, complex actions and the intentions guiding them may result simply from interacting with the physical world (Brooks 1990). Intention arises from the physical. Removing intention from the innumerable phenomenological pings that constitute daily experience eviscerates design of meaning. Therefore, can design thinking really occur without an essential umbilical cord to the physical world? If not, then design intention is always physically bounded and embodied; bounded by experience and embodied by our individual mental models resulting from, â&#x20AC;&#x153;descriptions that are task dependentâ&#x20AC;? (Brooks 1990). We cannot easily invent symbols of our intentions that are then translated into things. We cannot easily, or possibly ever, understand our context without actions; our intentions without the world. The intent is the thing itself and there is no intent without a physical context. Yet, is there some level in which it is possible to design without an umbilical cord to the physical world? Is it possible to formulate a coherent and robust set of design priorities independent of explicit physical attributes? On the one hand, the answer must be yes because the same design intent can certainly align itself with one or another distinct and contrasting physical manifestation. Notions of

transparency, solidity, closure, lightness, can be achieved in an infinite number of physical architectural constructs. The design intent is not bound to any particular material justification and thus the intent may be distinct from any particular material pathway. On the other hand, even these concepts imply an experience, a spatial and temporal dance performed in the physical world. Can the design intent be stated at a higher level, without the implication of experience? Can higher-level design intent emerge without the context of the physical world, without reference to the spatial or temporal? It is possible, though only mildly useful, to argue for example that the highest ideals of society such as freedom, happiness, welfare, may be considered spatially and temporally dimensionless. These ideals do not imply the material and therefore designing with such thoughts in mind does not necessarily imply a physical intent, albeit aside from the fact that all cognitive processes occur within and are derived of interaction with the physical world. 33

In addition, design in some fields may proceed without a decidedly physical intent. In design fields that do not directly produce physical artifacts, it is reasonable to expect that overtly non-physical design thinking is commonplace. The design of algorithms, services, procedures, telecommunications protocols, networks of various kinds and non-physical arrays may achieve productive results without direct reference to or need for material intention. Architectural design is different. Can there be architectural design without physical intent? Probably yes, for some small subset of architectural design focused on netherworlds of never-to-be-realized landscapes, such as the work of Lebbeus Woods or the walking cities of Archigram. However, the complete architectural enterprise necessarily applies itself to the physical world in a comprehensive way, precisely because it derives its initiation and motivation from the accumulated learning of actions in time as modulated, to take just one perspective, by light and space (Scully 1993). In fact, the specification of the spatial and temporal elements of architectural design intentions defines an autonomous enterprise exclusive to the discipline. Designers from other fields may disagree with this statement but the fundamental and autonomous nature of architectural design is affirmed in the simple intent to provide shelter for society. No other design discipline is charged with attending to this essential human and cultural need. The functional value of this charge is obvious, while the commanding dignity of the cultural import of the simple and, oh so complex act of providing shelter for human civilization can be found equally in exalted works of architectural genius and a multitude of nameless spaces of beguiling allure. While this may again not always involve a specific site or location, or any real spatial or material attributes, the architectural design project does insist on grounding in the physical world with intent to influence that world. Several philosophies of design have been predicated on the fundamental nature of location and space as driving elements of architectural design. From Alexander Pope and Christian Norberg-Schulz to the work of Utzon and Aalto, and the writings of Tzonis, LeFaivre and Frampton, the engagement of the architectural design discipline with the meaning of specific spatial and cultural locations, and the fundamental meaning of place is unparalleled. This is just one example of the complexity of architectural design thinking. One aspect of complexity is that the richness of the architectural design process stems from the multiple layers of cognition and representation that characterize the rise of the physical object out of the structured and unstructured framework of design thinking. In essence, the physical object is the vehicle through which architectural design intent is realized. In fact, the architectural design construct 34

often employs heuristic processes that actively promote interaction with form and material as a fundamental method of revealing and developing design intention. Therefore, one can take the position that architectural intention does not fully exist without interaction with the physical artifact – comprised of specific materials in a particular geometric configurations and produced under a specific set of conditions and processes. This argument would seem to lead directly to the statement that there is, therefore, no separation between design intentions and the resulting physical artifact. This statement would be easily defended if it were not also true that there is almost always a distinct difference between the intentions of the designer and reality; the physical presence of the artifact. In other words, though the artifact is essential in revealing the full complement of design intentions, it also retains an autonomy born of its material and volumetric specifications. In addition, the physical artifact is never a perfect representation of design intentions. There is always an ephemeral specter of the designer’s vision that escapes embodiment in material and geometry. Still, the richness of the products of architectural design, our greatest buildings and cities, is evidence of the intricate and deeply embedded motivations that drive the designer’s intentions and, in particular, the selection of materials to use in bringing the artifact into being. Architects are very good at aligning a diverse range of priorities into a coherent material agenda comprised of complex cultural systems and values and technical and economic performance. Though this essay promotes the notion that all architectural design is physically bounded and driven by the interaction between material artifacts and design thinking, a gap continues to exist between the current state of the world and the imagined vision of architectural speculation. One aspect of this gap is examined here; architectural thinking that ventures toward physical constructs that cannot be realized with a palette comprised only of known materials.

DESIGNER MATERIALS Generally, architects design with known and common materials; concrete and steel, wood and brick, glass and aluminum. Yet architectural visions often implicate uncanny phenomenological conditions through direct and indirect invocation of ambiguous and inherently unknowable material attributes. Sometimes an architectural vision is explicitly dependent upon unknown, unspecified or non-existent materials that depend on unlikely and even impossible material properties. The crystalline forms of Taut and Scharoun, the impossibly transparent glass towers of Mies van der Rohe, the geological scale of Fuller’s dome over midtown Manhattan and the mile high skyscraper of Frank Lloyd Wright are just a few well-known examples of the freedoms with which architectural visions are formulated and confidently promoted. These heroic visions do not hesitate to invoke an advanced technical future without any direct explanatory comment or any offer

FIGURE 1: As material property 1 and 2 are used to select specific materials (the black ellipses in the diagram on the left) material indices are graphed as diagonal lines, Ø 1, 2, 3. Traveling along any of these three material index lines indicates all material possibilities of comparable performance. Material properties under consideration could be density versus strength, embodied energy versus thermal conductivity etc. The curved dashed red line indicates the limit of combined material properties exhibited by all known materials. If the goal is minimization of both property 1 and 2, such as minimum embodied CO2 emissions and minimum cost for a predetermined structural application, any materials found toward the lower left hand corner will be preferred. Therefore, the area defined by the ellipse A contains within it, in the right hand diagram, two speculative options that are better candidates than any known materials. These two are theoretical materials, yet to be developed, and candidates for development for the particular mix of properties for the specific performance function.

of assistance toward realization. While the successful realization of such work may strongly suggest significant material innovation, the designer is often mute on the pathway forward. For example, the Miesian vision of a truly transparent tower has only recently been made possible with low-iron glass and the latest elastomeric sealants, and even then the reality has never quite met the vision. Ultra high strength concrete, highly compacted and reinforced with high strength “whiskers” has made super tall towers possible. The world’s tallest tower, the Burj Khalifa in Dubai stands at half a mile high, half as tall as Wright’s vision but, to be fair, only partly due to the technical challenges that remain. Either implicitly or explicitly, architectural design routinely invokes a speculative pressure toward materials that do not yet exist. One can understand this pressure as only one of many that push an architectural vision forward into new intellectual territory. This kind of work carries with it, at the very least, a specter of openended research; essentially architectural design as research (Anderson 1984). The new material innovations that are prompted by novel and sometimes radical architectural visions are part of this architectural research project but rarely attended to by those doing the imagining. So, is it possible that in addition to offering a vision, a designer may choose to play a role in achieving some material aspects of this imagined and technically advanced future? The answer is, for the most part, generally not. Builders and architects do not typically design materials themselves, though notable exceptions have been strongly influential. The bricklayer Aspdin was granted the intellectual property of inventing modern cement. After the industrial revolution and establishment of widespread manufacturing and research facilities much innovation became intensely technical. Today, a number of designers are co-inventing variations on earthen loam building materials, straw-bale and other natural fiber systems, glass and windows, metals, and other material systems. Rick Joy in Arizona, Grimshaw Architects, Foster + Partners, even Frank O. Gehry in association with A. Zahner Company have all brought material innovations to architectural design, though it must be acknowledged that this kind of innovation from the profession is extremely limited in comparison to the avalanche of output of industry. Today, the idea that

architects can have a primary role in the invention of new materials for buildings seems not only woefully unrealistic but also quaint and pretentious in the same breath. Why is this? First, each major material class is now attended to by an intensely technical sub-discipline of material science and engineering, chemistry, physics, and even biology; for example, polymer science, concrete science, ceramics and glass technologies, etc. All of these are mature, large-scale research and development communities with deep and extremely specialized expertise utilizing highly sophisticated and customized methods of analysis and tools of production. Second, many of these material classes have also spawned entire industries often populated with powerful and resourceful multinational companies; Dow Chemical, Dupont Plastics, CEMEX, Saint-Gobain, to name a few. Both of these kinds of organizations are able to deploy substantial resources and expertise to delve into the most technically challenging and narrowly defined aspects of the behavior and potential for innovation in specific material classes. Yet, it is not na誰ve or counterproductive to assert that the designer, as a small player in this arena, can play a pivotal role. As an interpreter and even author of a comprehensive vision prompting a new material future, the designer may initiate innovations in material formulations and combinations that best drive toward that future. Additionally, the designer may be well-educated in the performance demands and functional needs of building systems for contemporary buildings. For both these reasons, there need not always be a distinction between the dreaming visionary and the technically creative and powerful inventor. The challenges in doing so are obvious and regularly cited, so this essay will only list and not discuss them in any detail (Fernandez 2005). The lack of education in the material sciences and other science-based and technical training, the dominance of trade-based classification of architectural systems and practices, and the stubborn and immature intellectual class distinction between design and technical agendas in the academy and practice, all conspire to critically limit the potential for the architectural disciplines, and especially self-proclaimed designers, to contribute to material innovation. As part of this return to science the architectural discipline needs to deconstruct the trade-assembly classification of architectural systems and construct a science-based approach to fulfilling formal and aesthetic priorities. Regular calls have been made for a return to science and an understanding of the basis for assembly and system behavior resulting from specific material properties and interactions; something that the architectural profession generally lacks and that the academy imparts only partially. Equally important is the need for an understanding, by industry and technical specialists, of the aesthetic, cultural, economic and other disciplinary priorities that drive important formal agendas from within the design community; something the profession appreciates and the academy generates and supports but industry is generally ignorant and sometimes dismissive of. 39

FIGURE 2: A call to science in understanding basic material properties is essential for developing the expertise and facility in the architectural community to contribute productively to material innovation for buildings. Simple, but powerful concepts such as the relationship between material class designations (ceramics, metal, composite) and stress (ÎŁ) and strain (Î&#x2022;) are fundamental building blocks toward understanding building system behavior.

As the calls for a return to science are being made, in some quarters this call has been heeded. In recent years there has been a shift toward technical topics in architecture as the motivation and framework for design innovation. Some of this literature explicitly targets architectural materials (Manzini 1989) (Antonelli 1995) (Mori 2002) (Brownell 2010) (Schroepfer 2012). Still, today architectural material speculation is too often explored only rhetorically and with the language of philosophy rather than science. Without augmenting the qualitative discourse about architectural materials with a strategically defined set of analytical concepts and quantitative measures the design architect will continue to perpetuate a rather naĂŻve and quite limited ability to foster anything but incremental and generally aesthetically bounded and valued innovations. As evidence of this the architectural press continues to add to a rather large and somewhat redundant body of publications that address architectural materials from a decidedly qualitative perspective. This is an enduring legacy of the origins of our modern discipline of architectural design as an art that means only to apply, not necessarily integrate science. The call to a more serious engagement with hard science has also been rebuffed on the grounds that modern science in architectural work has too often led directly to the dilemmas we now face; global climate change and the depletion of resources alongside loss of cultural and regional architectural design identities and economies of construction. This is certainly a reasonable reaction. As an example, the invention of air conditioning has resulted in an addictive dependence on comfort at the flick of a switch, significantly contributing to global CO2 emissions while also relieving the suffocating and productivity-sapping heat and humidity of places like Singapore. It is the contorted legacy of modern science that we have only now begun to contend with the energy and emissions consequences of the rapid and global adoption of mechanized air conditioning. Lately though, the maturation of science in building design has also brought the architectural discipline much closer to an appreciation of strategies for constructing and operating buildings in ways perfected and hard won over millennia. Using natural ventilation, thermal mass, solar shading in an integrated mutually beneficial manner in architectural design can now be appreciated and applied with the assistance of computational simulation and visualization.

The change needed is simple. The notion of science as support for design must end. The notion of design as applied science must also end. The promotion of intellectual classes deserves retirement. Without this kind of change toward deeper intellectual maturity, there will continue to be a tendency to feel a general anxiety toward the direction and import of contemporary design.

NECESSITY AND INVENTION In schools of architecture across the United States and abroad, expressions of despair have been common refrains for many years. The discipline is losing relevance. The bulk of building construction is carried out without architects. Fees and salaries stagnated long ago and offer no prospect for dramatic increases anytime in the future. However, pronouncements of the death of the architecture have been regularly exaggerated. These fears of the health of the discipline can be traced back much further than just a few years and constitute periodic spikes of anxiety as change sweeps through the built environment. With the industrial revolution, component manufacture and standardization changed the nature of building components and assemblies. Architecture was dead. In the early 20th century traditional craft waned and wilted and to a great extent was purged from much of the production of builders in Europe and the United States. Later, the cult and fashion of modernism overtook the remaining vestiges of regional traditions and forms. Architecture was dead again. We find ourselves in a different kind of period. Today, it is more credible to announce the renewed health and growing importance of architectural design and production than to decry its continued value and relevance. At no point in the past 60 years, has architectural design held such promise and been charged with such a critical role in addressing several of the most pressing societal, environmental and cultural problems of the day. Two developments, one born of necessity and the other of invention, are most responsible for a reasonable optimism about the ability of the profession to deliver significant and lasting service to society. First, out of necessity, the practice of architecture has embarked on one of the most dramatic and broadly wrought transformations since the advent of the industrial revolution. The necessity to think of our world as defined by global limits has become a major cultural narrative driving every sector of the economy including construction, the built environment and infrastructure. The primary elements of this narrative are resources and population. The overriding framework is a notion of our world at the threshold of a new geologic era, the anthropocene. Central to this new world is our understanding of the flows of materials and the lifecycle burdens engendered by contemporary production and consumption. The limits to our global natural resources is evident; local urban water scarcity from Phoenix to Jordan, limits in rare earth metals, primary metals, construction minerals in some regions of the world, fossil fuels of certain types and variety of

flora and fauna. These limits are a direct result of increasing global affluence and growing human population. In 2012 we crossed the threshold into 7 billion and the UN predicts 9.3 billion in 2050, leveling off at some point around 10 billion (UN 2012). Furthermore, in 2008 the global population shifted from a majority residing in the country to a majority living in cities. Today, 3.5 billion people, 51.6% of the global population lives in cities. In 1950 the urban population of 745 million constituted 30%, and the UN predicts 5 billion urban residents, 60% in 2030. Uncertainty in these predictions is significant, but what is not contested is the growing urbanization and the likelihood of reaching a maximum total human population during this millennium. Contending with a world of resource constraints and intensification of urban agglomeration has brought real and sustained urgency to the architectural discipline as it serves to house people and provide facilities for businesses and industries in rapidly expanding and new cities. Second, out of invention a new path for understanding complex systems and generating and realizing physical artifacts has emerged and is serving to revolutionize the architectural design field. The digital revolution has brought together the virtual world and the physical. Computational power now offers enormous facility for simulation and modeling. In addition, computer assisted manufacturing and generation of form provide the designer with novel pathways toward design and construction. However, there is a danger of considering this revolution as leading to a design utopia. As with all revolutions, the outcome will bring new challenges that are difficult to anticipate. There is an unfounded enthusiasm for the panacea of digital design and fabrication tools and processes as a direct link between design intention and physical artifact. While advocates of computer enhanced and controlled design, prototyping and manufacturing suggest a closer relationship between the cognitive and the physical; this is only the case in certain arenas. For example, recently an artist has developed the technology to produce a 3D print of an unborn fetus for the expectant parents to hold, months before the actual birth date (Lopes Dos Santos 2012). The ultrasound image is made physical through 3D printing, but this is not the same as linking design intention with physical realization. This does not substantiate a closing of the design thinking-material realization gap. That gap persists. FIGURE 3: The site of extraction and processing of a major building material; a concrete plant on the banks of the Hudson River, New York State. It is now well known and widely accepted that the production of cement globally contributes a significant percentage of total anthropogenic CO2 emissions; upwards of 8 percent. (photo: J. Fernandez). 44

FIGURE 4: Two momentous trends of the 20th century. On the left, sometime around 1960, global materials extraction became dominantly nonrenewable for the first time in human history. This is very much a reflection of the sociometabolic transition from agriculture to industry as well as the enormous additions to That is, because in design there is still a leap to be made; a synthetic convergence infrastructure and the built environment serving a leading to an original proposal launched from the platform of analysis and steadily urbanizing global examination toward the speculation of an alternative future. This leap embodies population; shown on the the gap, the separation between analytical and synthetic activities in design. right. Also for the first Despite several decades of work in this direction, computation has thus far not time in history the worldâ&#x20AC;&#x2122;s shown credible evidence of fundamentally closing this gap and subsequently population became majority refocused much attention on tools that improve communication among stakeholders, city dwellers, sometime embed more information into virtual and physical objects and provide intelligent around 2008.

design guidance for enhanced performance along multiple axes (Colquhoun 1969) (Chok 2011, for example). The difficulties of a resource-constrained world and the capacities inherent in a digitally enhanced design environment make more possible than ever the development of critically-minded and technically astute architects. This will be our greatest challenge.

This essay is dedicated to the work of Timothy Cooke, SMArchS 2012, MIT.

REFERENCES

Anderson, S. 1984. Architectural design as a system of research programmes. Design

Studies, Volume 5, No. 3, pp. 146-150. Antonelli, P. 1995. Mutant Materials in Contemporary Design: MOMA. Museum of Modern Art, New York City. Brooks, R. 1990. Elephants Don’t Play Chess. Robotics and Autonomous Systems, volume 6, issues 1-2 :pp. 3-15. Brownell, B. 2010. Transmaterial 3: A Catalog of Materials that Redefine our Physical

Environment. Princeton Architectural Press, Princeton, NJ. Chok, K. and M. Donofrio. 2011. Abstractions for information based design. International

Journal of Architectural Computing, Volume 8, Issue 3: pp. 233-255. Colquhoun, A. 1969. Typology and the Design Method. Perspecta, Volume 12: pp. 71-74. Dym, C.L., Agogino, A.M., Eris, O., Frey, D.D., and L.J. Leifer. 2005. Engineering Design Thinking, Teaching, and Learning. Journal of Engineering Education, Volume 94, Issue 1, pages 103-120. Fernandez, J. 2005. Material Architecture: emergent materials for innovative buildings

and ecological construction. Architectural Press, Oxford, UK. Hevner, A.R., March, S.T., and J. Park. 2004. Design Science in Information Systems Research. MIS Quarterly, Volume 28, No. 1L pp. 75-105. Horvath, I. (2004) A treatise on order in engineering design research. Research in

Engineering Design, Volume 15, Issue 3: pp. 155-181. Lopes Dos Santos, J. 2012. The Foetus Project. PhD viva. Design Products MA course at London’s Royal College of Art, accessed online on September 14, 2012 at: http://www.dezeen. com/2009/07/16/the-fetus-project-by-jorge-lopes-dos-santos/ Magee, C.L., Wood, K.L., Frey, D.D., and D. Moreno. 2013. Advancing Design Research: A “Big-D” Design Perspective. ICoRD ’13, International Conference on Research into Design, Indian Institute of Technology Madras, 7-9 January, 2013.

Mori, T. 2002. Immaterial/Ultramaterial: Architecture, Design, and Materials. George Braziller, New York. Manzini, E. 1989. The Material of Invention: Materials and Design. MIT Press, Cambridge, MA. Schroepfer, T. 2012. Material Design. Birkhauser Architecture. Scully, Vincent (1993) Louis I. Kahn and the Ruins of Rome. Engineering and Science, 56 (2). pp. 2-13. UN. 2011. World Urbanization Prospects, the 2011 Revision. UN, Department of Economic and Social Affairs, Population Division, Populations Estimates and Projections Section, accessed online on September 16, 2012 at: http://esa.un.org/unpd/wup/index.html.