CASTonCAST: Superficies arquitectónicas complejas a partir de componentes prefabricados apilables

[EN] This article introduces the CASTonCAST system for the design and production of architectural freeform shapes from precast stackable components. This system is composed of two complementary parts: a novel manufacturing technique of precast stackable building components and a new geometric method for the design of freeform shapes by means of stackable solid tiles. This paper describes both parts of the system by means of physical prototypes and geometric studies. Guardar / Salir Siguiente >[ES] Este artículo presenta el sistema CASTonCAST para el diseño y la producción de superficies arquitectónicas complejas a partir de componentes prefabricados apilables. Este sistema está compuesto por dos partes complementarias: una innovadora técnica de fabricación de componentes prefabricados apilables y un nuevo método geométrico para el diseño de superficies complejas a partir de baldosas sólidas apilables. Este trabajo describe las dos partes del sistema mediante prototipos físicos y estudios geométricosWe would like to give special thanks to the LafargeHolcim Foundation for Sustainable Construction for supporting this project with two international awards: 1st Europe Next Generation award 2011 and 3rd Holcim Innovation award 2012. Furthermore, we would like to thank the Architectural Association School of Architecture and in particular our tutors Yusuke Obuchi and Robert Stuart-Smith for their encouragement and support during this research. Finally, we would like to thank Rafel Jaume Deyà for his helpful advice on the geometric method.Enrique, L.; Cepaitis, P.; Ordoñez, D.; Piles, C. (2016). CASTonCAST: Architectural freeform shapes from precast stackable components. VLC arquitectura. Research Journal. 3(1):85-102. doi:10.4995/vlc.2016.4291.SWORD8510231De Larrard, F. Why rheology matters. Concrete International, 1999, 21(8).Khoshnevis, B., Hwang, D., Yao, K. T., & Yeh, Z. (2006). Mega-scale fabrication by Contour Crafting. International Journal of Industrial and Systems Engineering, 1(3), 301. doi:10.1504/ijise.2006.009791Lasemi, A., Xue, D., & Gu, P. (2010). Recent development in CNC machining of freeform surfaces: A state-of-the-art review. Computer-Aided Design, 42(7), 641-654. doi:10.1016/j.cad.2010.04.002Liu, Y., Pottmann, H., Wallner, J., Yang, Y.-L., & Wang, W. (2006). Geometric modeling with conical meshes and developable surfaces. ACM Transactions on Graphics, 25(3), 681. doi:10.1145/1141911.1141941Lim, S., et al. Fabricating construction components using layer manufacturing technology. Global Innovation in Construction Conference, Loughborough University, Leicestershire, September 2009.Lloret, E., et al. Complex concrete structures: Merging existing techniques with digital fabrication. Computer-Aided Design, 2014.Podolny, W. and Muller, J.M., Construction and Design of Pre-stressed Concrete Segmental Bridges. New York: John Wiley & Sons, 1982.Pottmann, H., Schiftner, A., Bo, P., Schmiedhofer, H., Wang, W., Baldassini, N., & Wallner, J. (2008). Freeform surfaces from single curved panels. ACM Transactions on Graphics, 27(3), 1. doi:10.1145/1360612.1360675Pottmann, H., Liu, Y., Wallner, J., Bobenko, A., & Wang, W. (2007). Geometry of multi-layer freeform structures for architecture. ACM SIGGRAPH 2007 papers on - SIGGRAPH ’07. doi:10.1145/1275808.1276458Pronk, A., Rooy, I.V. and Schinkel, P. Double-curved surfaces using a membrane mold. IASS Symposium 2009: Evolution and trends in design, analysis and construction of shell and spatial structures. Valencia, Sept. 2009.Schmieder, M. and Mehrtens, P. Cladding freeform surfaces with curved metal panels: a complete digital production chain. Advances in Architectural Geometry. Wien: Springer, 2012.Vaudeville, B., et al. How irregular geometry and industrial process come together: a case study of the "Fondation Louis Vuitton Pour la Création", Paris. Advances in Architectural Geometry. Wien: Springer, 2012

On initialization of milling paths for 5-axis flank CNC machining of free-form surfaces with general milling tools

We propose a path-planning algorithm for 5-axis flank CNC machining with general tools of varying curvature. Our approach generalizes the initialization strategy introduced for conical tools [Bo et al., 2017] to arbitrary milling tools. Given a free-form (NURBS) surface and a rotational milling tool, we look for its motion in 3D to approximate the input reference surface within a given tolerance. We show that for a general shape of the milling tool, there exist locally and generically four 3D directions in which the point-surface distance follows the shape of the tool up to second order. These directions form a 3D multi-valued vector field and its integration gives rise to a set of integral curves. Among these integral curves, we seek straight line segments that correspond to good initial positions of the axes of the milling tool. We validate our method against synthetic examples with known exact solutions and, on industrial datasets, we detect approximate solutions that meet fine machining tolerances. We also demonstrate applicability of our method for efficient flank milling of convex regions that is not possible using traditional conical tools.RYC-2017-2264

Performance based pavilion design: a dialogue between environmental and structural performance

This paper investigates the design process of a performance based pavilion from concept towards construction phases, by challenging conventional form and fabrication techniques. The proposed project is considered as a temporary structure, located in Antalya, Turkey. A free-form structure and a parametrically defined cladding are designed to serve as an installation unit, a shading element and urban furniture. The pavilion geometry, performance assessments and proposed fabrication schemes are clearly described in the paper. The method integrates form, performance, material and fabrication constraints and exposes how environmental and structural performances, including Solar Access Analysis and Static Structural Analysis, may inform the design project.publisher versio

Computational Design and Parametric Optimization Approach with Genetic Algorithms of an Innovative Concrete Shading Device System

Office buildings in contemporary architecture usually have a high value of window to wall ratio (WWR) determining transparent façade as the most important part of the building façade to control solar gains, thermal losses and visual comfort. Therefore, in order to fulfill strict National energy regulations and LEED requirements, façades require a proper balance between transparent and opaque or shaded surfaces to avoid overheating, optimizing daylighting aspects and outdoor perception. Concrete is usually used in building sector for primary structure or secondary structure of cladding solutions. With new concrete materials and innovative digital fabrication process is possible to rediscover concrete for high performance façade/shading solutions. The aim of this paper is the development of high performance concrete static shading system using computational design approach and its optimization, by genetic algorithms, based on several parameters such as radiation control, outdoor view and daylight indexes and energy performance. After the development of a geometry definition managed with a parametric modelling approach (Rhinoceros and Grasshopper), genetic algorithm optimization were used in order to define the openness's sizes and their cutting angle to minimize solar radiation entrance during year, maintaining outdoor view. The possible geometric alternatives were part of a sensitivity analysis with Radiance and Energy-plus engine to assess the shading system performance in terms of daylighting and energy use. In order to evaluate their performances a study case, a single office unit placed in Milan (Italy) was defined, considered with wall facing outdoors, having a WWR of 86%, and five surfaces adiabatic. The results shows that using this approach is possible to develop an effectiveness shading solution able to control radiation over the year and likewise guarantee a high performance regarding the outdoor perception and visual comfort

Volumetric Procedural Models for Shape Representation

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Discrete Differential Geometry

This is the collection of extended abstracts for the 26 lectures and the open problems session at the second Oberwolfach workshop on Discrete Differential Geometry