Research On Parametric Design For The Form Of Free-Form Surface Architecture Based On Projective Cast

The development of digital technology and its widespread use in architectural design has led to a change in architectural thinking,methodology,and ways of working.It has stimulated the imagination and creativity of architects towards freeform approaches,enabling them to move away from two-dimensional thinking and towards the exploration of three-dimensional spatial forms.Using an orthogonal drawing system based on vertical projection to describe and design non-orthogonal free-form surface architectures has become a pressing issue in architectural design and construction.Stereotomy,a method developed in the Middle Ages for the design and fabrication of curved vaults and elements,is essentially a morphogenetic mechanism that uses projective drawing to depict the manual process of design to fabrication.This mechanism is closely linked to design and fabrication.Graphic statics facilitate the integration of architecture and structure.Through manual diagramming building,form is directly related to stress flow.This results in a force-generated approach to form-finding.However,both stereotomy and graphic statics fell out of favour because of the manual work required.This changed with the emergence of computer-aided design techniques.At the same time,the development of computer-aided design made it possible for architects to use parametric modelling and quantitative analysis to design non-orthogonal free-form surface architecture.This paper draws on the combination of graphic statics and stereotomy with parametric techniques to create informative models and data processing to increase the accuracy of the description and design of free-form buildings.These allow architecture and structure to be integrated and design and fabrication to develop in an integrated manner.First,the thesis explores the geometrical origins and development of graphic statics and stereotomy.These are based on the concept of projective cast proposed by Evans,taking architecture,structure,design,and fabrication as a starting point.With the aid of digital technology,graphic statics and stereotomy are integrated into a collaborative parametric design mechanism based on the principles of projective cast.This mechanism enables the translation of the projective cast concept into a practical design principle.Second,a parametric design process and design method for free-form architecture based on projective cast is established,starting from the principles of graphic statics and stereotomy.The conventional parametric design process is divided into three stages: design input,design execution and design output.Based on these,the transformation of the parametric design process by the structure-first approach of graphic statics and the build-first approach of stereotomy is discussed.A cascading design process that captures the synergy between graphic statics and stereotomy is constructed to provide a general framework for the subsequent design.The parametric design approach is based on form-finding,spatial tessellation and discrete units to design the morphology of free-form surface architectures,enabling their spatial transformation from surface to body.Finally,this thesis compares the equilibrium analysis of historic buildings with the applied analysis of new buildings.It summarizes the differences in the design process and extends the application of equilibrium analysis of historic buildings in the fields of restoration and conservation.At the same time,the design practice of using free-form ice shells is used as an example to systematically apply the constructed parametric design process and method.This is based on projective cast for parametrically designing the ice shell form and assisting in its fabrication,thus verifying the feasibility of the design process and design method.The study of free-form surface architecture is a theoretical exercise exploring the inheritance and development of traditional theories in the context of digital technology.It provides a reference for the integration of traditional theories and parametric technology for better design and fabrication.At a practical level,the parametric synergy mechanism of projective cast helps architects integrate performance design in the design phase and achieve architectural and structural unity.At the same time,the parametric model provides a preview of the built structure and feeds back into the design phase,facilitating the integration of design and fabrication.