Advances in Architectural Geometry 2014

Frontmatter

Simulation of Aggregate Structures in Architecture: Distinct-Element Modeling of Synthetic Non-convex Granulates

Abstract

Aggregate Architectures are full-scale structures made from large numbers of non-convex, geometrically interlocking designed granules. They form a novel class of material systems which are in many ways directly opposed to conventional architectural assembly systems. Whereas in an assembly structure both local parts and global formation can be clearly defined, aggregates can only be observed in their behavior as a granular mass. Thus one of the core challenges in working with granulates is the development of appropriate tools of observation. Both experiments and simulations are applied and need to be used in combination with each other. In this context the paper will present the most recent development of Distinct-Element Modeling (DEM) Simulations for Aggregate Structures. Previous results have been presented in terms of the geometric principle used to compute the individual grain and its contacts. The new results shown here lay their focus on developing accurate models simulating the construction process as well as specified load cases. Initially the overall field of Aggregate Architecture will be introduced. Consequently a brief description of Distinct-Element Modeling in general and for non-convex granulates in specific will be given. The exact modeling approach for a large excavated dome structure will be introduced both in its concepts and detailed parametric settings. The results of this simulation will be discussed and areas of further developments indicated.

Karola Dierichs, Achim Menges

Post-tensioned Discrete Concrete Elements Developed for Free-form Construction

Abstract

This paper presents a method for the construction of non-uniform precast concrete shell structures from unique parts. A novel method of discontinuous post-tensioning is introduced which allows tension to be taken through the connections. This increases the formal possibilities of the system beyond compression-only funicular forms. It also allows live loading to be catered for without significant thickening of the structure. Most significantly, the post-tensioning system allows for an almost total elimination of falsework a significant impediment to the realistion of complex shell structures. This advancement reduces resources needed for assembly, and increases the overall robustness of the system.

Also presented are a series of refinements that add to the geometric precision of individual concrete elements cast in lasercut PET moulds. These include the development of a casting rig used to fix casting moulds in the right position during casting and algorithms to produce mold details to mediate between the unique components and the repeated rig forms.

The last design experiment is the most elaborate, demonstrating a pavillion structure which incorporates all areas of development. The successful execution of this design experiment allows us to conclude that the building system in its current state of development is ready to be tested in a scale larger than the typical research pavilion.

Ole Egholm Pedersen, Niels Martin Larsen, Dave Pigram

Modular Fibrous Morphologies: Computational Design, Simulation and Fabrication of Differentiated Fibre Composite Building Components

Abstract

The paper presents a bottom-up design process based on the transfer of biomimetic design principles and digital fabrication strategies for modular fibre-based structures, as demonstrated on a full-scale prototype pavilion. Following the analysis of the structural principles of the beetle elytra, the material differentiation and the morphologic principles of the biological role model are transferred into design and fabrication strategies. Simultaneously, developments of a coreless robotic winding method for glass and carbon fibre reinforced composite elements are incorporated into the design process. The computational set-up developed for the entire workflow is presented, showing the integration of structural analysis with digital simulation, which enables the automatic generation of the robotic winding syntax for individually differentiated components. The investigations, simulation, fabrication and assembly process, which led to the realisation of a highly efficient lightweight architectural prototype, are explained in the current paper.

Stefana Parascho, Jan Knippers, Moritz Dörstelmann, Marshall Prado, Achim Menges

Application of Hybrid Glass-Timber Elements in Architecture

Semi Continuous and Self-generative Glass Layering Structural System

Abstract

The following paper explores the application of hybrid timber-glass elements on semi-continuous architectural structures. The use of glass as a structural material opens multiple fields of investigations. Beyond structural matters and safety issues, architectural questions as functionality and spatiality are briefly addressed, since they are paired with the structural layout. Furthermore, the potential of a glass plate system of overlaying, but yet discontinuous glass elements is addressed in more depth. Geometrical specifications on the structural glass application are elaborated on and generalized into a ‘card house’ algorithmic discretization model. Through the design and fabrication of a ‘case study’, the parallel use and digital simulation and empirical physical testing are discussed. A further potential use in the construction industry of the system is debated.

Philipp Eversmann, Paul Ehret, Christian Louter, Manuel Santarsiero

Gaudi’s Puffy Jacket: A Method for the Implementation of Fabric Slump Casting in the Construction of Thin-Wall Funicular Vault Structures

Abstract

This paper describes a method for the production of thin-wall funicular (compression-only) structures from unique double-curved concrete components via a novel slump casting technique. The technique deploys fabric formwork within simple two-dimensionally cut frames to enable the efficient production of the unique parts necessary to tessellate form-found funicular geometries. Through the realisation of a high-tech / low-tech ecology of production, the paper seeks the reestablishment of generative pathways between each domain in the design-to-production cycle: architecture, engineering and fabrication. The method and resulting case study pavilions are situated within the historical trajectory of architectural form finding, specifically, the realisation of masonry vault structures.

Iain Maxwell, Dave Pigram

New Opportunities to Optimize Structural Designs in Metal by Using Additive Manufacturing

Abstract

An initial research has been carried out, exploring the opportunities of using the design freedom created by Additive Manufacturing in metal on structural elements. The application of Additive Manufacturing (AM) bears the potential of increasing efficiency and shortening lead time by reducing processing steps, material use and labor intensity.

The aim of this research is the exploration of AM technology potentials as a feasible and robust design and manufacturing solution for structural building elements. This research is based on the redesign of an existing node, applying the new production opportunities of AM. This resulted in insights into the different design steps involved and knowledge on process, costs and structural characteristics. The start was a topology optimization on an existing design for a structural node, followed by a further rationalized design for production. A comparison in aesthetics, structural behavior and costs has been carried out between the new design and the conventional design. The first results look very promising and the work will be continued to enable the use of these new opportunities in structural designs in the near future.

Salomé Galjaard, Sander Hofman, Shibo Ren

Interactive Modeling of Architectural Freeform Structures: Combining Geometry with Fabrication and Statics

Abstract

This paper builds on recent progress in computing with geometric constraints, which is particularly relevant to architectural geometry. Not only do various kinds of meshes with additional properties (like planar faces, or with equilibrium forces in their edges) become available for interactive geometric modeling, but so do other arrangements of geometric primitives, like honeycomb structures. The latter constitute an important class of geometric objects, with relations to “Lobel” meshes, and to freeform polyhedral patterns. Such patterns are particularly interesting and pose research problems which go beyond what is known for meshes, e.g. with regard to their computing, their flexibility, and the assessment of their fairness.

Caigui Jiang, Chengcheng Tang, Marko Tomičí, Johannes Wallner, Helmut Pottmann

Biomimetic Lightweight Timber Plate Shells: Computational Integration of Robotic Fabrication, Architectural Geometry and Structural Design

Abstract

The research presented in this paper pursues the development and construction of a robotically fabricated, lightweight timber plate system through a biologically informed, integrative computational design method. In the first part of the paper, the authors give an overview of their approach starting with the description of the biological role model and its technical abstraction, moving on to discuss the computational modelling approach that integrates relevant aspects of biomimetics, robotic fabrication and structural design. As part of the validation of the research, a full-scale, fully enclosed, insulated and waterproof building prototype has been developed and realized: The first building featuring a robotically fabricated primary structure made of beech plywood. Subsequently, the methods and results of a geodetic evaluation of the fabrication process are presented. Finally, as the close collaboration between architects, structural and geodetic engineers, and timber fabricators is integral to the process, the architectural and structural potentials of such integrative design processes are discussed.

Oliver David Krieg, Tobias Schwinn, Achim Menges, Jian-Min Li, Jan Knippers, Annette Schmitt, Volker Schwieger

Form Finding of Twisted Interlaced Structures: A Hybrid Approach

Abstract

Our study presents a set of form-finding procedures to explore curved structures made from interlaced panels. Interlacing introduces a particular coupling between assembly components which has to be formulated along with a pertinent flexible body model. We examine here a hybrid approach: panels are simulated a first time using an elastic rod model formulated within a constrained elastic energy minimization where user can virtually buckle, twist and interlace strip assemblies. A thin shell model dynamically integrated comes complementary to the rod approach in order to resolve intersections in case of panels colliding while interlaced. Some conceptual structures are presented to demonstrated the procedure.

Sina Nabaei, Olivier Baverel, Yves Weinand

A Graph-Based Approach for Discovery of Stable Deconstruction Sequences

Abstract

The aim of object pile deconstruction is to safely remove elements one by one without compromising stability. The number of combinations of removal sequences increases dramatically with the number of objects and thus testing every combination is intractable in practical scenarios. We model the deconstruction sequencing problem using a disassembly graph, and investigate and discuss search strategies for discovery of stable sequences in an architectural context. We run and compare techniques in a large-scale experiment, on various virtual scenes of architectural models composed of different shapes, sizes and number of elements.

Lukas Beyeler, Jean-Charles Bazin, Emily Whiting

Advanced Topology Optimization Methods for Conceptual Architectural Design

Abstract

This paper presents a series of new, advanced topology optimization methods, developed specifically for conceptual architectural design of structures. The proposed computational procedures are implemented as components in the framework of a Grasshopper plugin, providing novel capacities in topological optimization: Interactive control and continuous visualization; embedding flexible voids within the design space; consideration of distinct tension / compression properties; and optimization of dual material systems. In extension, optimization procedures for skeletal structures such as trusses and frames are implemented. The developed procedures allow for the exploration of new territories in optimization of architectural structures, and offer new methodological strategies for bridging conceptual gaps between optimization and architectural practice.

Niels Aage, Oded Amir, Anders Clausen, Lior Hadar, Dana Maier, Asbjørn Søndergaard

Computational Design and Construction of Notch-Free Reciprocal Frame Structures

Abstract

A reciprocal frame (RF) is a self-standing 3D structure typically formed by a complex grillage created as an assembly of simple atomic RF-units, which are in turn made up of three or more sloping rods forming individual units. While RF-structures are attractive given their simplicity, beauty, and ease of deployment; creating such structures, however, is difficult and cumbersome. In this work, we present an interactive computational framework for designing and assembling RF-structures around a 3D reference surface. Targeting notch-free assemblies, wherein individual rods or sticks are simply tied together, we focus on simplifying both the process of exploring the space of aesthetic designs and also the actual assembly process. By providing computational support to simplify the design and assembly process, our tool enables novice users to interactivity explore a range of design variations, and assists them to construct the final RF-structure design. We use the proposed framework to design a range of RF-structures of varying complexity and also physically construct a selection of the models.

Nicolas Mellado, Peng Song, Xiaoqi Yan, Chi-Wing Fu, Niloy J. Mitra

Surface Panelization Using Periodic Conformal Maps

Abstract

We present a new method to obtain periodic conformal parameterizations of surfaces with cylinder topology and describe applications to architectural design and rationalization of surfaces. The method is based on discrete conformal maps from the surface mesh to a cylinder or cone of revolution. It accounts for a number of degrees of freedom on the boundary that can be used to obtain a variety of alternative panelizations. We illustrate different choices of parameters for nurbs surface designs. Further, we describe how our parameterization can be used to get a periodic boundary aligned hex-mesh on a doubly-curved surface and show the potential on an architectural facade case study. Here we optimize an initial mesh in various ways to consist of a limited number of planar regular hexagons that panel a given surface.

Thilo Rörig, Stefan Sechelmann, Agata Kycia, Moritz Fleischmann

Geometrical Solution Space for Grid Structures with Double-Walled Edges

Abstract

This paper introduces a method for creating double-curved grid structures made out of flat components, where fabrication is limited to only 2-dimensional cutting, making complex architectural structures accessible to a wider audience at a lower cost. The focus of the paper is to identify the limitations and to map the geometric solution-space of the method for real world construction applications. A double-walled nature of the structure enables us to significantly reduce the geometric complexity of the grid structure’s nodes – instead of needing to find a combined geometric intersection for all edges meeting at a node, our solution instead requires determining a pair of adjacent planes at a time, as many times as a node’s degree. But if any of these pairs of planes around a node is torsioned relative to the node’s normal, then collisions might occur between different pairs of planes. This paper discusses the geometric solution-space under which such collisions are avoided, making the structural joints easy to build. As a proof of concept, we demonstrate the use of this method in a design-build pavilion that was realized at the Singapore University of Technology and Design in 2013.

Andres Sevtsuk, Raul Kalvo

Designing Symmetric Derivatives of the Miura-ori

Abstract

The Miura fold pattern, or the Miura-ori, is a flat-foldable origami tessellation with a wide range of engineering applications. In particular, the Miura-ori has been applied to the folding of deployable structures for various architectural applications, e.g. folding roofs and shelters. In recent years, researchers have proposed variations on the Miura-ori which change both geometry and functionality of the pattern.

We introduce a framework for the symmetric generalisation of the Miura-ori. We study the Miura crease pattern as a ‘pmg’ wallpaper pattern. We reduce the symmetry of the Miura-ori to obtain new patterns while preserving the flat-foldability condition at each node. We conclude that we are able to use the Miura-ori to systematically design a variety of novel patterns, through appropriate design variations on the original pattern.

Pooya Sareh, Simon D. Guest

Algorithmic Optimization of the Cross-Section Distribution Across a Steel Framework Structure

Abstract

The main goal of the present paper is to introduce an algorithmic method that can be used in order to automatically optimize large spanning truss structures, such as stadium roofs and other large steel frameworks. Implementing such a method allows design to be freed from its dependence on the engineer’s work accuracy, not to mention the time saved. Therefore, it has proven to be very useful when it comes to comparing the influence of many parameters within a short lapse of time, allowing several people to work on the same project and compare results.

Lucas Lombard, Jérôme Lalande, François Consigny

Planar Panelization with Extreme Repetition

Abstract

No satisfactory general solution exists today to enable high repetition of elements in architectural freeform structures. In this paper we investigate why and propose several solution approaches to design highly repetitive structures with the simplest (and usually most affordable) geometric base elements: planar polygons. We explore the potential and limitations of these approaches and show that there is a large class of structures achievable by repeating even only a single polygon. We discuss how the proposed techniques reach beyond the topics of repetition and panelization and could be part of a more diversified investigation of “freeform” in architectural geometry.

Mathieu Huard, Michael Eigensatz, Philippe Bompas

Interlocking Folded Plate: Integrated Mechanical Attachment for Structural Wood Panels

Abstract

Automatic joinery has become a common technique for the jointing of beams in timber framing and roofing. It has revived traditional, integrated joints such as mortise and tenon connections. Similarly, but only recently, the automatic fabrication of traditional cabinetmaking joints has been introduced for the assembly of timber panel shell structures. First prototypes have used such integrated joints for the alignment and assembly of components, while additional adhesive bonding was used for the load-bearing connection. However, glued joints cannot be assembled on site, which results in several design constraints.In this paper, we propose the use of dovetail joints without adhesive bonding, on the case study of a timber folded plate structure. Through their single-degree-of-freedom (1DOF) geometry, these joints block the relative movement of two parts in all but one direction. This presents the opportunity for an interlocking connection of plates, as well as a challenge for the assembly of folded plate shells, where multiple non-parallel edges per plate must be jointed simultaneously.

Christopher Robeller, Andrea Stitic, Paul Mayencourt, Yves Weinand

The Ongreening Pavilion

Abstract

This paper describes the work of Ramboll Computational Design during the design and construction of the Ongreening Pavilion timber gridshell. The structural approach involved form-finding bending-active timber laths, connected at intersections to form a doubly curved shell. The resulting form was simple to fabricate and assemble, realised using 6.5 mm thick Finnish birch plywood laths that could achieve high curvature while maintaining desired strength. Due to the random nature of the final lath topology, the resulting structure was extremely stiff in spite of its low material weight, acting similarly to a continuous monocoque. The fully demountable shell was first erected at Ecobuild 2014 in London.

John Harding, Will Pearson, Harri Lewis, Stephen Melville

The Caterpillar Gallery: Quadratic Surface Theorems, Parametric Design and Digital Fabrication

Abstract

The use of certain quadratic surface theorems has mainly been associated in architecture with the design of classical vaults, domes and piping. The work presented by the authors is intended to explore the potential of these theorems to be used in the generation law for more complex shapes in contemporary architecture. The paper shows the case study of a built full-scale prototype, The Caterpillar gallery, a project stemming from the combination of geometric research and teaching innovation.

Formal and structural experimentation take place in this project where, by starting from geometrical considerations, an efficient way of generating longitudinal spaces is proposed. One of the mentioned theorems applied to rotational cones provides the starting point for the generation of a set of concatenated surfaces that, once assembled, constitute a very stable self-supporting structure with a variety of possible applications.

Roberto Narváez-Rodríguez, Andrés Martín-Pastor, María Aguilar-Alejandre

Constructing Complex Geometries: A Case Study on the Cité des Civilisations du Vin in Bordeaux, France

Abstract

A number of geometric optimization were applied to the Cité des Civilisations du Vin in Bordeaux, France. The façade is comprised of a curved panels attached to wood laminated, also called glulam, beams.

The purpose of this paper is to describe the research to construction process undertook by Vinci Construction France as part of the contracting consortium for the project when dealing with geometries involving concrete, laminated wood, glass panels and metallic panels.

Benjamin Soquier, Raphael Mizzi, Daphné Dureisseix, Jean-Baptiste Valette

The Geometry of the Error

Abstract

This paper focuses on the importance of error in the evolution of form and the logic of matter distribution describing its relationship to randomness and repetitive behaviour. Using the logic of cellular automata systems on the origin curves of body formations, it displays a methodology for the creation of errors. Extracted cloud points are used as meshing guides for geometries that display a fine game balance between organization and disorder.

Through a series of experiments, a taxonomy of bodies’ deviations and morphological errors is created resulting in a tooling system that can be applied in various scales and conditions according to the parameters specified, providing alterations to body form, optimization, and varied possibilities for interaction with the context, environment and other bodies.

Yota Adilenidou

LAR-ABC, a Representation of Architectural Geometry from Concept of Spaces, to Design of Building Fabric, to Construction Simulation

Abstract

This paper discusses the application of LAR (Linear Algebraic Representation) scheme to the architectural design process. LAR is a novel representation scheme for geometric design of curves, surfaces and solids, using simple, general and well founded concepts from algebraic topology (Dicarlo et al., Comput Aided Des 46:269–274, 2014). LAR supports all topological incidence structures, including enumerative (images), decompositive (meshes) and boundary (CAD) representations. It is dimension-independent, and not restricted to regular complexes. Furthermore, LAR enjoys a neat mathematical format, being based on chains, the domains of discrete integration, and cochains, the discrete prototype of differential forms, so naturally integrating the geometric shape with the supported physical properties. The LAR representation find his roots in the design language PLaSM (Paoluzzi et al., ACM Trans. Graph 14(3):266–306, 1995; Paoluzzi, Geometric programming for computer aided design. Wiley, Chichester 2003), and is being embedded in Python and Javascript, providing the designer with powerful and simple tools for a geometric calculus of shapes. In this paper we introduce the motivation of this approach, discussing how it compares to other mixed-dimensionality representations of geometry and is supported by open-source software projects. We also discuss simple examples of use.

Alberto Paoluzzi, Enrico Marino, Federico Spini

Offset Folding

Abstract

Facing a growing world population and a general economic model which focuses on growth on the one hand and on respectively decreasing limited natural resources on the other, the issue of resource efficient construction becomes more and more important in architecture and building industry. It is well known that double curved structures represent one of the most efficient principles of natural design, as shell structures are able to fulfil different requirements with a minimal consumption of material. Implementing large scale spatial curvature in a world full of the linear and flat products inherent to mass-production is one of the most discussed structural topics of the last two decades in architecture and civil engineering. This paper presents a new, structural approach to implementing resource efficient double curved structures using flat panels. The basic idea is to utilize a quasi-double-layer system by folding rhombic quadrangular panels and connecting them with a simple plug-connection which is stiffened by the different spatial orientation of neighboring elements. As a result it is possible to create a wide range of semi-permeable structures which are adaptable double curved surfaces.

Alexander Stahr, Hannes Löschke