Development of a new connection system for reticulated shell structures using parametric modeling and digital fabrication.

• Autor(a) principal: Oliveira, Isabel Moreira de
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
• Texto Completo: http://www.teses.usp.br/teses/disponiveis/3/3144/tde-26112019-124340/
• topic: CAE; Conexões estruturais; Connection system; Estruturas reticuladas; Grid shell; Gridshell; Joint; Parametric programming; Programação paramétrica; Reticulated shell; Sistema de conexão

Lightweight structures in grid form made of bar elements joined together with nodes reticulated shells, or gridshells. Different gridshell structural systems are studied, and a new connection system and method for generating this system are proposed. The connection system applies to structures with surfaces that have a high variability of curvature and connection parameters. Prior to the development of such a connection, the choices of materials, existing types of connections, grid patterns, cladding systems, optimization methods, and structural analysis evaluation are presented. Each enumerated aspect enables a well-reasoned development of the connection. The connection uses standardized hub geometries and interconnecting parts. The bars of the structure connect to the hubs through these interconnecting parts, which absorb varying parameters of the connection, such as incidence angle, twist angle, adjacency angles, and the fabrication tolerance of bar lengths and bolted connections. The aim is to provide a system that can be assembled quickly, disassembled and reused. A parametric modeling environment is used to model global and local geometry of meshes and nodes. Inputs for the programmed parametric definition include a mesh, geometry of the hub notch, and bars cross-sections; outputs include bar lengths, interconnecting parts geometries, and assembly information. A structural stability analysis is conducted with parametric finite element software. A small-scale physical model is presented, serving as a proof of the concept developed within the computational modeling environment. The scalability of the model is discussed, taking as a starting point the experience of the production of the small-scale model. Tensile tests results of the printed material and connection are provided.