Advanced Chapters of Structural Design

Hanging Models - Formfinding of Structures Based on Physical and Digital Modeling

Original Image Link The importance of the subject of hanging models for architects originates from the need to understand the interrelation between the force and the shape by means of simple tools that satisfy a mechanical basis within the structural behaviour in compression.
Hanging models enable the designer to determine the optimal form of structures carrying loads purely in compression. It is based on the known principle of inverse and doesn’t require any special knowledge in geometric computing and numerical methods of optimization.
The seminar intends to deal with the topic from different perspectives, and focuses on the two main approaches of physical and digital modelling. The technique of using physical models for form-finding was inspired basically by Gaudi’s philosophy. Previously, less sophisticated attempts were made by Heinrich Huebsch and Giovanni Poleni. The design free-form shell roofs based on physical hanging models were extensively used by Swiss engineer Heinz Isler beginning in 1954 who pioneered shell structures with minimal thickness. The seminar introduced the methods and materials used in the by Gaudi, Isler, Tomlow, and others, more attention were made  to benefit from today’s available modelling materials, as well as, stiffening the hanging model to be presented in an inverse form.
In addition to the physical tools, the seminar deals with the state of the art digital tools for optimal form finding approaches based on hanging models. Several methods were proposed for digital hanging modelling, namely: Dynamic Relaxation, Particle-Spring systems, Finite Elements, Force density method and Thrust Network Analysis. The seminar was focused mainly on two digital tools to be used by students for modelling of free form shells. The first is RhinoVAULT, which is a plug-in for Rhino developed at the BLOCK Research Group. This tool can be used for the design of efficient freeform shells based on the Thrust Network Analysis. The second is Blender which is free and open-source 3D computer graphics software. The soft body tool based on Dynamic Relaxation in Blender has been used efficiently for hanging modelling. Short tutorials for the use of both digital tools are added to this report in Appendixes.
The students worked in small groups during the seminar to establish their own hanging model forms. This cooperative environment gave them the possibility to explore their own intellectual capabilities and to develop problem-solving strategies. Several oral stage reports were presented during the seminar by each group. The presentation environment was very suit to foster critical thinking and to share the ideas and encourage each other with their excitement as well as practicing the skills of effectively communicating technical information.

Lecturers

Prof. Dr.-Ing. Wolfram Jäger
Dr.-Ing. Tammam Bakeer 
Dipl.-Ing. Alexander Peinlt