Shaken but overlooked: efficiency, economy and elegance in earthquake-prone areas

Are structures outside of the Euro-American canon being overlooked when we discuss structural art? In an essay that was selected as one of three finalist submissions for the 2018 SOM Structural Engineering Travel Fellowship, Tim Michiels argues through examples from Japan and Mexico, that extraordinary structures built in earthquake-prone areas do not always receive the attention they deserve. 1. Celebrated structural art is underrepresented in … Continue reading Shaken but overlooked: efficiency, economy and elegance in earthquake-prone areas

How to describe the esthetics of structural surfaces? (2/2)

In an earlier post, I wrote about how and why we seem at loss for words when describing the esthetics of a structural surface. I continue that discussion here and analyse what vocabulary layman use and make suggestions for where we might seek additional jargon. I  build my argument upon the results of an experiment carried out by graduate student Rebecca Napolitano in Fall 2016 on the Princeton University Campus.  In the physical experiment, a membrane was installed on a highly frequented location on a central location next to a neo-gothic medium size building.The  membrane was shown in an existing built environment, which might have caused distraction from observing the pure membrane form, but allowed for a full 3D perception of the membrane deforming in the wind.  Randomly selected 138 undergraduate students who passed by the installation, were asked to describe the membrane structure with one word.  If their response coincided with an already recorded word, they were prompted for another defining word.

This physical experiment yielded a plenitude of words which can be catalogued according to formal analysis or subjective response classes. The first category, formal analysis, is grounded in the fine arts and Vitruvian architecture tradition. This type of analysis disassociates itself from reactions such as elation, fear and awe.  These words describe emotions or subjective responses and constitute the second category.  The subcategories in both classes were pre-established before the collection of data and are based on the ones discussed by [1].

Formal Analysis

We first investigated the vocabulary pertaining to the category of formal analysis. This category holds the subcategories of form, proportion, space and visual mass.

Observing the 3D form of the membrane is not a simple process. In the past, built form has been discussed as a hierarchy of simple forms combined according to rules, into an assembly of complex forms [2].  The words in the experiments refer either to the simple or the complex form or the rule.  Simple form descriptions in Rebecca’s experiment included words such as “round”, ”bulbous”.  Complex form descriptions included  “nurbs”, ”free form” and rules included “tangent continuity”, “cambered”, “periodic”, “smooth”, “logarithmic”, “interlacing”, “weaving”, “optimized” , ”linearly disruptive” and “bendy”.

Nurbs, non-uniform rational basis spline (image credit

The subcategory proportion evaluates the geometric relationships between the different parts. Traditionally formal rules for proportioning have been defined buildings composed out of analytical forms including hemispheres and cylinders. Unfortunately, they are not that relevant for force-modeled systems such as the membranes in the experiments, because these membrane geometries are far more complex.  These geometries are generated by the laws of physics and are more difficult to proportion and steer than analytical ones.  A few words like “contrived complexity” hinting at these characteristics, showed up in the experiment.

A number of words in the experiments related to space.  The observers understood space as the Aristotelian idea that the membrane created both a positive space and a negative space or “embrace and grows space”. Words like “encompassing“ (positive space, the membrane itself) and, “limitless” and “unconstrained” (negative space, the space that co-exists separately alongside the space occupied by the membrane itself) exemplified the subcategory space.

Visual mass as opposed to actual mass can be achieved by the perceptions of light, color and texture. The untrained observer tends to make a connection between visual and gravitational mass.  Previous studies show how white surfaces, such as the one in the physical experiment, and the smoothness of the membrane in the experiment helped the structure as being perceived as lightweight [1] . These perceptions were captured in the experiments in the words “sinuous” and “slim”.

Subjective Responses

Besides the words that fall in the category of formal analysis, we closely examined the second category, called subjective responses. The results showed that the observers felt that the membrane has a certain character that spoke to them.  The words were distributed over the subcategories anthropomorphism, sensuality allusion, physical security and empathy.

Some observers saw the membrane as a living creature (eg. “sting ray”, “cocoon”) and endowed it with personality and intent. This association is called anthropomorphism.  The membranes were also perceived as “pregnant in the breeze”, “in bloom” and “about to take flight”.

Many observers found that these surfaces had a sensuous quality and captured those impressions in words like “sensual”, “voluptuous” and “calliphygian”. These words refer to the movement of the membrane as it progresses to a visual climax, followed by a relief of tension. In particular the inward and outward curving membrane surfaces have a particular sensual quality, which is missed by forms with single curvature.

Some spectators covertly or indirectly referred to an object from an external context.  The membranes evoked allusions with words such as “Rubenesque”. This word for example refers to the works of the Baroque painter Pieter-Paul Rubens (1577-1640) and means plump or rounded in an attractive way.  Other images included poetic metaphors such as “symphonic”, “motion frozen in time”, “essence of motion”, “natural choreography”.  Other allusions included scientific, artificial natural associations such as “meniscus”, “satin/silk, “hilly” and “motion of water”. These references to physical objects, although they are not grounded in the innate perception of the observer, contributed to aesthetic experiences while viewing the membrane.

Anthropomorphism, an association to a sting ray (left ), allusions to Ruben’s works (right), ,silk (bottom right) and hilly (bottom left) call the membrane in the wind to mind without mentioning it explicitly. (image courtesy Flickr the Commons)

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