As technology advances, architects often employ innovative, non-standard shapes in their designs for the fast-growing number of high-rise buildings. Conversely, climate change is bringing about an increasing number of dangerous wind events causing damage to buildings and their surroundings. These factors further complicate the already difficult field of structural wind analysis. Current methods for calculating structural wind response, such as the Eurocode, do not provide methods for unconventional building shapes or, in the case of physical wind tunnel test and in-depth computational fluid dynamics (CFD) simulation, they are prohibitively expensive and time-consuming. Thus, wind load analysis is often relegated to late in the design process. This paper presents the development of a computational method to analyze the effect of wind on the structural behavior of a 3D building model and optimize the external geometry to reduce those effects at an early design phase. It combines CFD, finite-element analysis (FEA), and an optimization algorithm in the popular parametric design tool, Grasshopper. This allows it to be used in an early design stage for performance-based design exploration in complement to the more traditional late-stage methods outlined above. After developing the method and testing the timeliness and precision of the CFD, and FEA portions on case study buildings, the tool was able to output an optimal geometry as well as a database of improved geometric options with their corresponding performance for the wind loading.

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Wind analysis for the structure of buildings is a challenging process. The increasing strength and frequency of wind events due to climate change only add higher demands. In addition, high-rise buildings are growing in number and include many of unconventional shape. Current methods used in practice for calculating structural wind response either do not account for these geometries, such as the Eurocode or are prohibitively time-consuming and expensive, such as physical wind tunnel tests and complex Computational Fluid Dynamics simulations. As such, wind loads are usually only considered towards the end of design. This paper presents the development of a computational method to analyse the effect of wind on the structural behaviour of a 3D building model and optimise the external geometry to reduce those effects at an early design phase. It combines Computational Fluid Dynamics (CFD), Finite Element Analysis (FEA), and an Optimisation algorithm. This allows it to be used in an early design stage for performance-based design exploration in complement to the more traditional late-stage methods outlined above. The method was implemented into a rapid and easy to use computational tool by combining existing plugins in Grasshopper into a single script that can be used in practice on complex shaped parametric high-rise building models. After developing the method and testing the timeliness and precision of the CFD, and FEA portions on case study buildings, the tool was able to output an optimal geometry as well as a database of improved geometric options with their corresponding performance for the wind loading allowing for performance-based decision-making in the early design phase.@en

This paper presents a detailed structural analysis of a bubble shell engineered by Heinz Isler. Through 3D scanning the geometry of this shell structure has become available to the authors. Structural analysis has not been possible before since the geometry of the shell was not available. The bubble shell was Isler’s most built type of shell. In the paperfirst the process of reverse engineering the geometry of the shell is described. Second, the effect of pre-stress in the edge beams is described. Third, the load distribution throughout the shell and the membrane behaviour relative to bending behaviour is assessed.@en

This article describes a collaborative and interdisciplinary initiative aiming the design, optimization, and construction of a water tower prototype for the victims of a natural disaster. The students of Architecture of Wroclaw University of Science and Technology, Poland, were challenged to use paper tubes to provide a design solution with enough strength to be used in a post-earthquake scenario. After the initial designs, seismic response of the proposed towers was evaluated using a custom-made shaking table. The selected tower was then studied parametrically to obtain the most suitable geometry, in terms of preventing overlapping of building parts and easiness of construction. The final three-day intense process of construction and assembling of a 1:3 scale tower prototype provided the researchers and students with insights about connection details when using paper tubes. The initiative continues to explore the potential of applying pro-ecological material for temporary facilities covering basic needs after natural disasters.

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This paper investigates the symbiotic relationship between the architectural appearance of a bridge and the structural design. The research is done by reviewing and comparing the design methodology employed by the first author in the conceptualization of two of his bridges; an early work from 1997 and a recent work from 2017. The review of the early work describes a design methodology that could be described as intuitive design, whereas the later work is the result of computational from-finding and optimization. Parallels are drawn and the historical development of the toolbox of the architect and the engineer is described. The paper analysis the way the two designs were achieved by looking from the perspective of the architect and that of the engineer, two disciplines that nowadays closely work together on the design of a bridge. The paper concludes by identifying the key design considerations to achieve a beautiful yet structurally sound bridge. The question whether beauty can be the sole result of a rational design process towards the most efficient form according to the laws of mechanics, is addressed. This paper demonstrate the belief that when it comes to the design of a bridge, architecture and structure, form and force, are involved in an interdependable and symbiotic relationship.@en

The paper presents an ongoing research about the design and a possible use of a responsive flexible mold. The mold is developed by integrating its precedents with automation and Human-Computer Interaction (HCI). The objective of the design is to provide an immersive design tool which has direct link to fabrication. It allows intuitive interaction to its user in order to help with the design and production of complex forms by supporting the designer's implicit skills with computer. The paper presents the design by illustrating the use of the hardware such as the actuators, the sensor and the projector; and by defining the workflow within the software. The paper concludes with the description of a possible use case in which the system is used to design and materialize an object in different scales.@en

The ShArc is more than just a bridge from A to B; this bold design will become a destination in itself and a cultural landmark for the metropolitan city of Berlin. The tripod shaped bride is located at the intersection of the Spree with the canals Charlottenburg and Landwehr, connecting Charlottenburg with Moabit. The ShArc is a hybrid structure that combines the slenderness of an arc with the stiffness of a shell. The three members of the bridge are connected at the peak of the arc geometry. At that point the deck becomes a public platform where people can enjoy panoramic views of the surroundings. In order to reduce the deck weight in that area and to maintain the open character, an opening has been created in the deck directing the pedestrian flows around the void.For a structurally effective geometry the deck is designed with a significant double curvature. In the cross-section the deck is a U-shaped half-pipe. The sides reach a maximum height at the middle of the span and also serve as a railing. In some areas, perforations are created to create views on the water and on the skyline, combining structural optimization with transparency.@en

Practical implications of deforming a flat mould surface into a double-curved shape. Proposal for processing concrete elements with a complex double-curved geometry in an efficient and accurate manner using parametric, associative modelling.

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Many free form shell structures that have been designed and build in previous decades are fascinating structures. We can learn from these structures by analysing them and studying their structural behaviour. However, in some cases the geometry of these structures is not available; most notably the shapes of shell structures designed and build by Heinz Isler, who has built over 1400 shells. The geometry of many of his scale models and build structures have been obtained by the authors by making use of 3D laser scanners which create point clouds. This paper presents a method for reverse engineering of free form shell structures from point cloud to finite element model. Since shape and force interact, special attention is given to the geometric accuracy. Every model must be sufficiently accurate. The method has been applied to data obtained by scanning Isler’s shells. Important aspects that influence the quality of the resulting finite element model are described.@en

The precise geometries of three reinforced concrete shell roofs have been measured with a laser scanner. The resulting point cloud has been modelled by NURBS surfaces. Two methods have been developed for determining the shape imperfections with lengths between 0.5 and 5.5 m. The largest observed imperfection amplitude is 80 mm with length of 5 m. The imperfections are represented by a variance spectrum and an extreme value distribution. From this are derived a formula for the characteristic imperfection amplitude and the partial safety factor.@en