Thick Funicular: Particle Spring Systems for Variable-Depth Form-Responding Compression-Only Structures

Particle-spring systems are commonly used to develop compression-onlyform finding systems. This paper proposes to use a particle-spring systemto respond to a desired form in order to generate a variable-depth, compression-only structure. As a variable-depth system, loads can be re-directedthrough the depth of material in order to result in a desired form, as opposedto a structurally optimal form that assumes a uniform thickness approach.This paper proposes to generate, build, and test compression-onlystructures in response to a desired architectural geometry. This researchwill allow for integration with external programs to input a desired form, andresult in a constructible compression-only structure.Thin-shell compression-only structural systems are relatively new to thebuilt environment. Compression-only structures on the other hand are ancient.Thin-shell structures assume a minimal and consistent cross-section.This assumption is driven by material efficiency. The results are forms developedexclusively by structural concerns (typically gravity), hence the termform-found. Architecture has to respond to structural concerns, but it alsohas to address a variety of other issues — acoustic, formal, program, etc.It is not necessary for form to be driven strictly by structural requirements.For example, Gothic Cathedrals contain the thrust-vector within the variabledepth of the stone’s cross-section. These Cathedrals are not determined byidealized catenary form, but through a confluence of architectural desireswith compression-only principles. With this approach as inspiration, thispaper addresses the potentials of compression-only systems to be resolvedthrough a variable-depth in order to obtain a desired form.Much research has been done in analyzing existing variable-depth structuresto determine if a thrust vector falls inside the depth of material (Blocket al, 2006). Other methods assume a fixed depth of material in order togenerate a design. The method proposed in this paper assumes a desiredgeometry and allows for a variable thickness to re-direct the thrust vector asa means to produce a viable design that concerns both structure and otherformal concerns. If typically one assumes thin, this paper assumes form.This method is dedicated to addressing architectural concerns with structuralresults. This paper does not advocate for the reversion to a past architecture.It promotes the insertion of lost knowledge into our current meansand methods of making.

Volume Editors
Martha Thorne & Xavier Costa

ISBN
978-0-935502-83-1