the ground as an excited field

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THE GROUND AS AN EXCITED FIELD

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THE GROUND AS AN EXCITED FIELDProfessor Alejandro Zaera-PoloPrinceton Envelope GroupLIMITS_Context, groundLucas Suárez Alperi

The problematic of contextualization has long been discussed in the dis-cipline. Regardless the will of the architect, every time an object is built; it establishes a relationship with the context. It might be against the context, for the context, or acknowledging an existing urban fabric.

However, gravity defines a directional relationship that ties the building to the ground and defines a syntactical form of the structure that explicitly resists that action. In this sense, the building will always be a contextual object, independently of the importance that the architect gives to the authenticity of it.

There are different means through which the building can gather authen-ticity. It might be contextual, material, experiential, phenomenological … but they are all related to the status of the ground. Therefore, grounding defined as the way in which the building is rooted becomes a political state-ment to a question that has historically been answered in different ways.

Whatever political form the ground takes, it defines a domain of power to which the building is attached. The tectonics that the building displays in order to transmit the gravitational loads and engage the ground define a cultural discourse with political implications that go from Le Corbusier’s in-finite datum in Ville Savoye to the elevated stage in the Farnsworth House by Mies van der Rohe.

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PETER EISENMAN, Holocaust Memorial.

JEAN NOUVEL, Copenhagen Concert Hall

JOSÉ ANTONIO CODERCH, Casa Ugalde.

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ERIK GUNNAR ASPLUND, Extension of Gothenburg’s City Hall.

ÁLVARO SIZA, Leça de Palmeira pools.

PETER ZUMTHOR, Vals termal baths

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DANIEL LIBESKIND, Jewish Museum. Garden of Exile.

Collage of Eisenman’s and Libeskind’s Berlin project.

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Jeff Kipnis defines the three main attitudes through which the relationship between the power and the subject were challenged and approached by the architects of Modernism through the articulation of the ground. Le Cor-busier, Mies and Wright developed their own paths in order to confound the relationship of architecture with instantiated power.

The first attitude is the conceptual model. Le Corbusier defines a diagram that produces the disestablishment of the ground as land, turning it into an infinite datum. The horizontal window, the pilotis, the free plan, the free façade and the roof garden are the 5 points for an architecture of revolution that is really ambitious on its attempt to disestablish the land as a politically charged ground. The structural use of the pilotis here seems crucial for the disestablishment because of their blank nature. Colums, as opposed to pilotis, categorize space through the lens of narrated gravity, since one can identify a top and a bottom. However, this experiment has proved to be naïve to a certain extent and has remained in the realm of the conceptual.

The second attitude relates to the performative diagram. Mies van der Rohe displays an architecture that puts the subject into a character. The political implications of this characterization of the individual have historica-lly been related to the institutions of power. Therefore, this politically char-ged technical device can either serve the power or challenge the clichés of what an institution should be characterized like.

One can find an example of this challenging attitude in Rem Koolhaas’ Seattle Public Library, where architecture acknowledges its own power to undermine the institutional power in a move towards casting against type. As a matter of fact, one can feel the difference between the eroticism and power disestablishment offered by Seattle’s public library as opposed to the traditional model of the Neoclassical model, e.g. Madrid’s Public Library by Francisco Jareño de Alarcón.

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Reproduction of Jeff Kipnis’ diagrams.

LE CORBUSIER, Ville Savoye.

IKTINOS & KALLIKRATES, Athens’s Parthenon.

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MIES VAN DER ROHE, Farnsworth House.

FRANCISCO JAREÑO DE ALARCÓN, Madrid National Library.REM KOOLHAAS, Seattle Public Library.

Collage of equivalent interiors in both libraries.

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Within the peformative diagram, the ground is no longer datum; it beco-mes a stage. Mies concedes the fact that there is a ground that is politi-cally saturated as land. He does not try to change it into a datum or field. However, while the subject is characterized the effect of disestablishment of the ground as land and rendered into datum is achieved. In that sense, it differs from Le Corbusier if we take into account that the effect only lasts whilst on stage. In order to accomplish his aim, Mies does not touch the ground; hence he needs the staircase.

Thus, the staircase and the front door conform the apparatus that takes you to a space which takes the subject to a stage where many characters can perform; acknowledging always that the individual will eventually take the staircase down and come back to land. Logically, the projects that ope-rate under this premise will have very strong staircases, very strong doors, and much more transparency.

The third attitude described by Kipnis deals with new authenticities. Frank Lloyd Wright works within this frame and engages the ground empowering it as land. The building states its placement on the site, acknowledging the land as a political substract of the building that feeds it with authenticity and tries to be continuous with it.

In the Robie House, the perimeter bench surrounds and widens the building so as to render it as geological extension of the ground. Wright uses the articulation of the dichotomy ground-roof not only to empower the ground as land, but to engage locality as well. The building belongs to a certain location. The duality of the cantilevered roof that shades the upper part of the façade and the powerful brick sockle that emphasizes the horizontality of the project and adds qualities of land as earth, defines a political statement: Earlier with the Prairie model and more lately with the Usonian (a term that he coined himself),

By defining the concept of Usonia (abbreviation for United States of North America), Wright embraces the idea of a new landscape, architecture and urbanism for North America as a land that entails new content and asks for a housing model of its own: USA as a new authenticity; thus free of pre-vious architectural conventions.

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FRANK LLOYD WRIGHT, Kaufmann House.

FRANK LLOYD WRIGHT, Robie House. Prairie.

FRANK LLOYD WRIGHT, Rosenbaum House.

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In the late 60’s, Lina Bo Bardi was able to sythesize the three grounding attitudes of Modernism in the Museum of Art of Sao Paulo.

The building is sited in a privileged city location, an intersection of superpo-sed traffic routes: the Avenida Paulista and the Avenida 9 de Julho Tunnel. On one side is the Trianon Park and on the other the Vale. In this spot there used to be a belvedere belonging to Trianon Park which had been donated by a private citizen to the Sao Paulo City Council with the provi-sion that no building would interfere with the view of the city from the park.

Lina Bo Bardi’s radical solution consisted of organizing the program in 2 parts: one raised, aerial and crystalline and the other semi-buried, surroun-ded by gardens and vegetation. The empty space between the two buil-dings completes the definition.

Therefore, we find the three masters in the same project. Corb’s infinite datum is the result of the raising of the volume on top of the red pilotis. Furthermore, the void becomes a horizontal fenetre for the Trianon park. The Miesian staircase that puts the subject into a character takes you into the institutional milieu of the art gallery. Finally, Wright is represented by the semiburied building, empowering the land by the engagement with the topography and the use of textured concrete and vegetation.

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LINA BO BARDI, MASP. Aerial views from (left) and towards (right) the Trianon Park.

LINA BO BARDI, Transversal section of MASP.

LINA BO BARDI, MASP. Aerial view of the Aveni-da Paulista (left) and Av. 9 de Julho (right).

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Transversal section of MASP. Corb’s diagram.

Transversal section of MASP. Mies’ diagram.

Transversal section of MASP. Wright’s diagram.

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Collage of Bo Bardi’s and Corb’s works.

Detail of the access stair.

Detail of the half-buried part of the MASP.

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The datum becomes a refuge to the city and a potential receptacle for many political contents. It performs as a place of encounter, of exchange: antique fairs, political meeting, music concerts, art exhibitions, … In that sense, the MASP is the only breathing space, the only pause, on this long Sao Paulo avenue., completely surrounded by tall buildings. Actually, Lina thought about it as a John Cage’s silence.

Hence, the space was designed as infinite, as a limitless museum. Howe-ver, this idea had a structural implication that led to a box with a 70-me-ter span, 29 meters wide and 14 high, supported by 4 concrete pillars 8 meters above the ground. Lina agrees here with Frampton’s Critical Regionalism by presenting a structural poetic with no faked representation in the façade. The syntax of the form explicitly describes how it is resisting the action. Two central beams are propped on consoles on the pillars and support both the decking and the second floor that are hung by the use of cables (which allows for a very slim slab). Finally, two precast-concrete beams sustain the roof decking from above. The effect is a pillar-free art gallery and light-filled box in which the painting seem to float.

Consequently, it can be concluded, that one of the main features of this model is the great structural effort that it entails and the political implica-tions that the action of liberating the ground may have; in other words, the generation of a void. In the case of Bo Bardi’s project, the sociological and economical density of the Avenida Paulista takes action in order to acti-vate that space, and by doing so, the failure of many out scale Modernist projects is prevented.

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Collage of Bo Bardi’s and Corb’s works. The infinite datum.

Photograph of MASP’s covered plaza during a concert.

Photograph of MASP’s structure during construc-tion process.

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The MASP could be considered, as we have described, a good culmina-tion of the attitudes of the building towards the ground as explored by the masters of Modernism. The project could also be considered a touchstone against which the tendencies of contemporary operations with the ground could be understood.

Contemporarily to Lina Bo Bardi’s project, in the France of the 60’s, we find a counter response to the Modernist articulation of the ground: Ar-chitecture Principe’s “The function of the oblique”(by Claude Parent and Paul Virilio).In their 1960’s work, Architecture Principe proposed a critique of orthogonality. Parent and Virilio suggested going beyond the realm of the Euclidean geometry on which historical architecture had been built, towards a non-linear, non-Euclidean geometry: topology.

“Weight and gravity are key elements in the organization of perception. The notion of up and down linked to earth’s gravity is just one element of perspective […].

As soon as one starts to incline planes and to get rid of the vertical, the relationship with the horizon changes. Gravity does not come into play in the perception of space in the same way at all. When one stands on an inclined plane the instability of the position changes the relationship to the horizon. The idea is that as soon as a third dimension (the oblique) is brought into the relationship with regard to space and weight changes, the individual will always be in state of resistance –whether accelerating as he is going down, or slowing down as he is climbing upp, whereas when one walks on a horizontal plane weight is nil (or equal). The idea was to work with gravity in a new way; to create a vision of instability while the perspec-tive is stable. You see this clearly in the case of drunkenness –when you are drunk and start to move around the whole world starts moving, percep-tion is moving with the body. Here the structure of the ground moves… a gravity or gravitational drunkenness! You could call it a kind of “eroticiza-tion” of the ground.”

So Virilio introduces here the possibility of a diagonal that links the vertical and the horizontal. Consequently, he claims the erosion of the segregation phenomena he had observed in the horizontal (the village and the ghetto) and the vertical urban orders (the tower as the vertical ghetto). The oblique function defines a new urban order, where the politics of space- namely the social relations involving authority or power- relate to the politics of geometry rather than to the politics of geography.

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GROUPE ARCHITECTURE PRINCIPE, Circula-tion habitable.

GROUPE ARCHITECTURE PRINCIPE, Geome-try of the oblique.

GROUPE ARCHITECTURE PRINCIPE, Diagram describing the energy processes of the oblique.

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GROUPE ARCHITECTURE PRINCIPE, Diagram describing dynamics of the oblique.

PAUL VIRILIO, Landscape.

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In the 1980s, “The function of the Oblique” as a theory materialized in the experiences of Deconstructivism. New ways to engage the ground were introduced and that opened the possibilities for new political definitions of ground not only as land or datum, but as field, urban field and metropolitan field as well. A new cultural discourse for ground was needed, since it had become mobile. The modernist diagrams were rendered tactical, and what used to be centrifugal (datum) became centripetal (field).

The way in which the building engages the ground determines the proper-ties of the field, i.e. the field conditions. As outlined by Stan Allen in “From Object to Field”, a field condition is a “formal or spatial matrix capable of unifying diverse elements while respecting the identity of each”. Thus, the boundary conditions of a field are less important that the local intercon-nectivity between the individuals of the field –like the birds in a flock or the demonstrators in a crowd-.

The precise rules of classical composition based on organization of the whole in a hierarchical top-down fashion -such as symmetry or axiality- leave room for a new set of democratized operative strategies based on bottom-up models: the field conditions.

Therefore, if we think of the figure as an effect that emerges from the field itself, the interaction of the object and the ground defines a series of moments of intensity: vortexes, peaks, protuberances… within the same continuous field. Moreover, the relative positions of the volume of the ob-ject to the ground, that is: exterior, tangent, secant and interior; may entail changes in those different levels of potential entropy whenever the field is activated by use.

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ZAHA HADID, Vitra fire station.

ZAHA HADID, Cincinnati Contemporary Arts Center.

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A flock of birds.

Demonstrators in front of Terragni’s Casa del Fascio.

The relative position of the object to the ground.

OPEN EXTERIOR

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OEOPEN EXTERIOR

PROJECT_DEFINITION/

The building is sited in a privileged city location, an intersection of superposed traffic routes: the Avenida Paulista and the Avenida 9 de Julho Tunnel. On one side is the Trianon Park and on the other the Vale. In this spot there used to be a belvedere belonging to Trianon Park which had been donated by a private citizen to the Sao Paulo City Council with the provision that no building would interfere with the view of the city from the park.

Lina Bo Bardi’s radical solution consisted of organizing the program in 2 parts: one raised, aerial and crystalline and the other semi-buried, surrounded by gardens and vegetation. The empty space between the two buildings completes the definition.

OPEN_EXTERIOR/The open exterior model generates an inhabitable space underneath the built volume by lifting the massing. This model has two main features: the program for the public space and the structural strategy that solves the large span requirements for such space. The “open exterior” disestablishes the ground as land and renders it as datum, following Le Corbusier’s conceptual diagram. The attachment of the building to the ground is punctual, for both access and structure. Therefore, the influence of the object on the field is less strong (3% of occupied area in the MASP).

ROOF BEAM

ROOF

ROOF RIBS

2ND FLOOR (ART GALLERY)

MAIN BEAMSTEEL HANGERS

PILLAR-BEAM CONNECTION

1ST FLOOR (CIRCULATION)

CONCRETE PILLARS

ECCENTRIC FOOTING

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SLOPE MAPS/ENERGY LEVELS

SLOPE THERMOMETER0 5 10 50 100

15%

0%

Mapping the slope of the ground would provide a range of energy levels, acknowledging that the steeper the slope, the more fatigue it would take to go up, and the more kinetical energy would be released when going down.

In this sense, it is interesting to compare the data with the different heights and the field maps, so as to obtain an variety of potential trajectories within the field.

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VECTOR FIELDS/INTERNAL LAWS

The different impact that the object’s “grounding devices” have on the field can be mapped by weighting the influences of those diverse components. As an example, the accesses perform as elements of attraction, and their importance can be weighted in order to differentiate the main entrances from the secondary.

Other elements that alter the field are public furniture, structural elements, courtyards, green areas, existing paths, ...

Finally, in order to visualize their performance, we may run a bidirectional grid that would absorb the different weights and reveal their behaviour.

Field Attractors (Access)

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Occupied areas (Structure/Access)

GROUND FLOOR DEVICES/ACCESS AND STRUCTURE

GROUND/ VOID vs SOLID

AREA SOLID = 140 M2AREA VOID = 4.410 M2

AREA TOTAL = 4.550 M2

% OF OCCUPANCY = 3%5 10 50 100

CLOSED EXTERIOR

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CECLOSED EXTERIOR

CLOSED_EXTERIOR/The closed exterior model does not touch the ground. However, it provides no room for inhabita-tion. This model works under the premises of Mies’ performative diagram: it is a stage. The main characteristics of the “closed exterior” are two: strong accesses (doors and stairs), and treatment of the processional landscape. The articulation of the building to the ground is based on surfaces, what allows for the use of a generic structure. In this scenario, the object has a very strong pre-sence in the field (100% of occupied area in Laban).

PROJECT_DEFINITION/

Laban proposes a solution to the works put forth by Corb, Mies and Wright. The building does not touch the ground, and by doing so it turns it into an undetermined datum. The subtle lift of the façade performs as the Miesian stair and allows the building to hover. Following the same argument, the green sloped surfaces that surround the perimeter never touch the building, which helps the characterization of the subject.

Finally, Herzog & de Meuron change the meaning of the front door as an element that stantiates the relationship with the ground. The doors are made continuos with the shadow gap that “lifts” the building. Besides, all the perforations are developed with the same language (reflective glass and aluminium mullions) in such a way that the semiotics of the door and the window are erased.

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0 5 10 50 100 SLOPE THERMOMETER

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AREA SOLID = 3.695 M2AREA VOID = 3.695 M2


% OF OCCUPANCY = 100%0 5 10 50 100

TANGENT

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TTANGENT

TANGENT/The tangent model operates as a hybrid of the two first models. This model generates a series of inhabitable spaces that are bounded by the topology of the building itself. This fact generates two man attributes: the microclimatic conditions of those interior spaces (usually associated with cour-tyards) and the geometric continuity (topological projects) or interruption (fragmented geometries) that provide different frames to assume the required spans. The “tangent” creates an intense report of the object to the ground (46% of occupied area in SANAA’s project).

PROJECT_DEFINITION/

One of the most important implications of the new cultural discourse for the ground, accelerated by the develop-ment of technological tools, has been the structural requirements that topological projects relate to. The Rolex Learning Center is multipurpose building related to a university. It is located in the center of a large green space and becomes the meeting point that concentrates both events and people.

The envelope consists of 2 parallel slabs that have slight undulations that generate a double curved surface that gets perforated by a series of interior courtyards. The courtyards have different sizes and a series of diverse programs attached to them. The elevated zones offer perspectives of the surroundings, the lake Léman and the Alpes. Therefore, the alterations designed by SANAA on the artificial topography are related to both climatic and programmatic requirements.

The different relationships of tangency that the envelope establishes with the ground, render the latter as a fragmented datum. The large flat horizontal envelope is deformed in order to facilitate cross ventilation; the use of courtyards produces microclimatic conditions that operate on the nature of the datum as whole, turning it into a series of spaces that have different climatic and programmatic conditions.

The subtle gestures result on an ambiguous new authenticity attached to the ground, that gets disestablished when the building curves up and gets consolidated when the envelope touches the ground. In this sense, the effect of the access is crucial. The building can be approached from the 4 sides by walking under a roof, that is in fact the artificial ground of the envelope. This is feasible due to the topological nature of the project.

STEEL FRAME

600 MM SHELL

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15%

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% OF OCCUPANCY = 46%0 5 10 50 100

SECANT

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SECANTS

PROJECT_DEFINITION/

As described by OMA, Agadir can be considered a “single building ‘split’ in two parts, a roof and a sockle, to create a major urban ‘room’, a covered plaza on the beach, facing the sea. The two axes culminate on the plaza. Floating above the verandah; the hotel: a single layer of rooms, each its own view. The coference center forms the lower part, the sockle…”

The project reinterprets the Islamic space through its materiality, its concave and convex shapes, its light shafts and the forest of variable diameter columns. The section, therefore, varies upon structural and programmatic demands. OMA’s Agadir Congress Hall is a tectonic landscape. The dunes in the exterior continue with the “hills” and “valleys” in the interior of the sockle, in such a way that it accommodates the largest components of the program: auditorium… It is not ground, or land, or datum. It is a programmed ground that acts as a localized urban field. Mirrored to the sockle, the same kind of relief appears on the roof where it accommodates the royal chamber. Thus, the plaza gets activated by the two curvilinear envelopes.

The materiality is crucial in Agadir. In this sense, the project tries to respond to the paradox claimed by Frampton: “how to become modern and to return to the sources; how to revive and old, dormant civilization and take part in universal civilization”. The floor and the ceiling of the veranda are formed by concrete ‘shells’, which have been cast upon the dunes, using the sand as a natural formwork. Ribs strengthen the shells and form patterns on the interior surfaces. The uppershell is supported by columns, which are different in height, thickness, and spacing. The lower shell and the roof are supported by vierendeel beams. Stability is achieved by means of the connection between the two shells combined with steel bracing. ‘Soft’ joints have been integrated between the columns and upper beams because of seismic considerations. The elevation and the roof, clad with polished and unpolished local stones, give the building its rock-like appearance.

Finally, the Miesian stair that surrounds three quarters of the building and leads to a plinth renders the plaza as a stage. It has a clear relation to Mies’ National Gallery in Berlin. However, even this artificial slab is activated by program, since it absorbs the parking that comes from a large highway. It conforms the main axis and becomes the secondary access to the lobbies of the building.

“The victory of universal civilization over locally inflected culture” described by Frampton is contested in Agadir. The project embraces the Critical Regionalism by mediating the impact of urban civilization with elements derived indirectly from the peculiarities of a particular place. not by the use of local architectonic features, but by the local customization of more abstract ones.

SECANT/The secant model engages the ground in a different way: the ground becomes a stratus of the object. In this sense, the articulation of this model relates to the model of new authenticities with which Wright used to work. However, the ground becomes here a field that is activated by the programmatic inputs received from the object, both from above and/or below. The role of the connections between the object and the field in the “secant” project is key. Access and structure may work up or downwards with different influence in the occupied area (7% in Agadir).

FULL STRUCTURESTRUCTURE UNDER COMPRESSION(both slabs are partially supported by columns)

STRUCTURE IN TENSION(both slabs are partially hanging from cables)

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% OF OCCUPANCY = 7%0 5 10 50 100

OPEN INTERIOR

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OIOPEN INTERIOR

OPEN_INTERIOR/The open interior model operates mainly inside the ground. The main consequences are programmatic and climatic. First, the roof becomes a large ground. Therefore, the use of green roofs, the articulation of public furniture and the accurate positioning of the accesses is crucial. Second, the fact of burying the whole program entails large ventilation and lighting requirements. In this sense, the green roof seems interesting as a solution. In the “open interior” model, the object’s structure has no impact on the field (0% of occupied area in Yokohama).

PROJECT_DEFINITION/

Yokohama’s Maritime Terminal is a collage of programs. It discovers new authenticities by gene-rating a roof that accommodates a transition space that is linked to the maritime stroll and creates a gate to the city. Like in Agadir, we find a programmed ground that absorbs complex movement diagrams in three interlocking levels.

In the tectonics of Yokohama, one can find an artificial landscape attached to the context by the introduction of the asphalt of the existing roads as the connection of the building to the city. The envelope becomes a centripetal field that has both urban and metropolitan scale. As a matter of fact, two elements in the roof describe this double nature: on the metropolitan scale, the wood that covers the whole topography comes from Brazil; as for the urban realms, the series of sun blockers are the answer to the local request for sun protection, since the Japanese are specifica-lly disturbed by the sun.

Therefore, Yokohama Terminal embraces, as an outcome of its own programmatic nature, the “endless processal flux of the Megalopolis” and bounds it in its diagram.

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VECTOR FIELDS/INTERNAL LAWS The different impact that the object’s “grounding devices” have on the field can be mapped by weighting the influences of those diverse components. As an example, the accesses perform as elements of attraction, and their importance can be weighted in order to differentiate the main entrances from the secondary.



Field Attractors (Access)Occupied areas (Structure/Access)


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SECANTOEOPEN EXTERIOR

0%

25%

50%

75%

100%

MASP (Lina Bo Bardi)

3%LABAN CENTER (Herzog&deMeuron)

100%ROLEX CENTER (SANAA)

46%AGADIR CENTER (OMA)

7%YOKOHAMA TERMINAL (FOA)

0%

CECLOSED EXTERIOR

TTANGENT

S OIOPEN INTERIOR

OBJECT TO FIELD RATIO/PERCENTAGE OF FOOTPRINT AREA BASED ON THE PROJECTION OF THE ENVELOPE OF THE BUILDING

SLOPE MAPS/HUMAN ADHERENCE AND COMFORT

15%

0%

SLOPE MAPS/VEHICULAR ADHERENCE

30%

15%

SLOPE MAPS/SPECIAL VEHICLES ADHERENCE

30%

50%

SLOPE MAPS/ARTIFICIAL ADHERENCE

50%

100%