Numerical Simulation And Applications Of The Inverse Hanging Method

New-form space structures represent one of the important developing directionsof morden space structures, and how to realize the harmonious of elegant form andreasonable performance of structures is the key problem for the design of suchstructures. Structural mophology which focuses on the relationship of form andforce of structures, provides the theoretical basis for the development of new-formspace structures. Due to the short developing history and multi-disciplinarycharacters, the study of structural mophology is still at the exploratory stage.The free-form structures are typical new-form space structures, and as theirexcellent visual impact and reflecting the diversification of architectural beauty,they have been the central issue of structural morphology. But how to realize theorganic combination of surface diversity and mechanical rationality in the process ofthe form-finding, which named form generation, is the principal problem indesigning free-form structures. The methods of the form generation can roughlydivided into two categories: the form-finding method based on model experimentsand the form generation method based on structural optimization. The formermethod played an important role at the beginning of the structure morphology, butwith the development of computer technology in recent years, the latter one hasbeen more attention. However, the form-finding method based on modelexperiments represented by inverse hanging method have many advantages, such asits clear concept, imaging directly, it’s still a kind of important means exploring thestructure morphology.In this paper, numerical simulation is used to realize theinverse hanging method for studying the experimental process, in order to dealwith the experimental law of similarity and the test precision and other commonproblems in those methods. In this way can we widen the scope of research of theinverse hanging method, and is advantageous to the comparison of different scheme.Considering those research condition, our object locates in the period of theselection of agricultural scheme and structural scheme, and have carried out someresearch works as follows:(1) the establishment of the numerical inverse hanging methodBased on the basic principle of the inverse hanging experiment, using nonlinearfinite element method and inverse iterative technique or dichotomy of ideas, to findthe equilibrium position of for the suspension cable or membrane structure, and thento establish the numerical form-finding method in order to achieve the zero momentstructure (or lesser curvaturemoments). On this basis, to improve the basic method, initially established the form generation method to consider the stress’s uniformityand the lightest structural weight respectively.(2) research on structural shape regulation method based on the numericalinverse hanging methodIn view of the defect which the structure form generated by the traditionalinverse hanging experimentation is relatively single, through in-depth analysis ofthe structural elements of the system, and taking into account of the basiccharacteristics of the established numerical form-finding method, we established thestructural morphology controling method based on the structural elements of thesystem reconfiguration, such as: by changing the parameters of the boundaryconditions, material parameters, load distribution,and so forth. In result we achievedthe diversification of the structural morphology, and divided it into two levelsconsidering the boundary conditions are clear or not.(3) research on mechanical properties of the inversed structure and theengineering application of these methodsThrough multiple inversing the hanging model experiments and the numericalresults were compared, creating many established typical building construction’sroofing structure, modeling for a building to be built to provide a variety ofreasonable morphology, analysising the mechanical properties of the inversedstructure, and analysising the mechanics rationality of the inversed structure fromvarious angles, so as to proved that the accuracy, effectiveness and applicability ofthe established numerical method, and to discuss the mechanical properties of theinversed structures preliminary.