Research On Parametric Design Method Of Long-span Architectures’Surface

As the development of computers, the parametric design tool has beenunfolding, but most people still think that it is a tool which can be used to design agreat many of free forms. Actually，designing architectures with free forms is one ofthe purposes of the parametric tool, additionally, it is also a design method whichcan help architects in all aspects and be used in every step of the architecturaldesign.Long-span architectures have three features which are different from othergeneral architectures, including strong structural conditionality, huge space volumeand strong cultural directivity. These features can be realized by the surface’s fourroles, such as functional role, ecological role, formal role and construction role.From the angle of the cognitive psychology, it analyzes the essence of the design’sobject, the thinking rule of the design’s subject as well as the advantages anddisvantages of the parametric platform in the design thinking. Based on thistheoretical foundation, it constructs the design method of the long-spanarchitecture’s surface and the specific design steps within the limits of theparametric platform’s ability. The steps are the parametric construction of thedesign requirements’ diagrams, the parametric construction of the designcontradictions’ solution order and the parametric realization of the design diagrams.From the aspect of the parametric construction of the design requirements’diagram, it sets up a complete recycling chain of the parametric design, which is“generation—examination—desicion”, and divides the parameters collected aroundthe design requirements into three categories: generation parameters, examinationparameters and decision parameters. In each segment of the design chain, itorganizes these parameters based on the thinking types of the “meta-design” inorder to increase the design efficiency.From the aspect of the parametric construction of the design contradictions’solution order, it analyzes the space structure and time structure of the threecontradictional systems (surface’s formal contradictional system, surface’s holecontradictional system and surface’s adhereing material contradictional system)based on the system theory. It also judges the difficulty level of the solution on thebasis of the contradiction types and solution methods. Then, it calculates theweightness of the different parties of a contradiction with the characteristic vectormethod in order to determine the solution order, meanwhile, the process can beprogrammed for automatic query.From the aspect of the parametric realization of the design diagrams, it establishes the classification rule of the data, the expression way of the data and thedesign method of the database according to the brain’s memory mode, and alsoshows various kinds of data inquiry of the material database, the structure databaseand the construction database. At last, it treats the inquiry result as a prototype andchanges its parameters for more forms of the long-span architectures’ surface.In a word, the paper treats the parameterization as a set of a series of tools andmethods to aid design thinking, and tries to tap its advantages in the computation,storage and visualization in order to reduce the number of the iteration and increaseeach one’s speed, so architects can input more time and energy into the creationwhich the computers cannot even replace.