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Additive manufacturing with the DED-arc process offers limited freedom in terms of the geometric shape of work pieces. The process and fabrication systems restrict the part geometry producible, which must be taken into account during design already. For this reason, a design process was investigated in which geometry generation is based on a self-organizing system. The aim of using a self-organizing system is the possibility to directly control the geometry-defining points. Next to load cases, the design method considers geometric boundary conditions from the production process when generating the geometry. In order to identify these geometrical constraints from production experimentally, a concept of Case Study Demonstrators was applied. This was used to investigate how path planning and production can be carried out for specific geometrical features and to identify restraints of the process and the manufacturing system, e.g., smallest producible wall thickness and overhangs. Subsequently, the obtained restraints were considered as boundary conditions for the design process and were included in the modification of an example geometry. By applying the presented design method, it was possible to maintain a minimum wall thickness throughout the structure while generating a topologically optimized geometry. In contrast to compliance with the minimum wall thickness, no satisfactory behavioral rule could be found for limiting the overhang. [ABSTRACT FROM AUTHOR]

The paper presents the design to construction process of an ultra-lightweight hybrid temporary structure consisting of a combination of bending-active glass fiber-reinforced polymers arches, a restraining system made of stainless steel cables, and a translucent membrane envelope. After a brief introduction to the basic design concepts and versatility of the modular system to create different shapes, the paper focuses on the fast-track erection procedure that enables to build the pavilion in a very short time. A multi-disciplinary team had collaborated at the design development of the temporary pavilion, built with the aim of deepening a wide range of aspects that are peculiar to temporary architecture. The aim of the second design-to-construction loop, following the first loop which resulted in the construction of the first full-scale prototype, is two-fold: firstly to optimize the innovative mix of lightweight structural components with the aim of reducing the total weight of the building (and thus facilitate transport and installation), and secondly to test the technical details designed to favor reversibility and to ensure the re-usability of the structure for multiple cycles of use. The paper concludes by showing the results achieved and the lesson learned from the first construction of the temporary pavilion in occasion of a one-week event and anticipating the further studies regarding the interface between structure and membrane envelope, also in relation to the building expected life-span and requirements. [ABSTRACT FROM AUTHOR]

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Copyright of Studia Slavica is the property of University of Ostrava, Faculty of Arts and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Existing BIM technologies do not provide links to product components that are needed to facilitate the participation of manufacturers in the design and building processes. A deeper integration between product component catalogues and BIM is necessary for this purpose. Through the Linked Data approach, information about building products can be obtained from multiple sources and linked to create semantic descriptions of components that can be retrieved from a BIM model via component catalogues. In this article, we present the case of an application of Semantic Web technologies to connect BIM models with a catalogue of structural precast concrete components, carried out within the research project BAUKOM. As a proof of concept we have implemented a service which accesses the information provided by the catalogue to assist the design team in the assembly and dimensioning of structural components during the project phase. [ABSTRACT FROM AUTHOR]

[Display omitted] • Interlayer boundaries and local minima and maxima of the surface profile do not generally coincide. • The waviness profile contains representative features of the surface topography. • Surface parameters describe the waviness resulting from different manufacturing parameters. Additive manufacturing of structural metallic components is an emerging technology. The DED-arc (direct energy deposition) process combines efficiency with high degrees of freedom and predictable quality. Compared to powder-based processes, the surface is relatively coarse as a result of high heat input and larger molten zones. In industrial applications, the post-treatment of surfaces of DED-arc components cannot be guaranteed for economic reasons or due to geometric constraints. Hence, the surface topography must be evaluated and quality levels need to be defined. Unfortunately, established surface parameters and their determination cannot be directly transferred to DED-arc components and further research on this topic is needed. This article demonstrates surface topography features of representative DED-arc components. Furthermore, waviness profiles were established by applying an alternative cutoff wavelength to better represent the DED-arc surface characteristics. Based on these waviness profiles, 2-dimensional height parameters were calculated. The waviness parameters were determined for four DED-arc specimens made from high strength wire electrodes. The manufacturing parameters were varied in terms of different energy input and interpass temperature, resulting in varying deposition rates and surface qualities. The waviness parameters correlated with manufacturing parameters. A mixed deterministic and random nature of the surface topography was verified. [ABSTRACT FROM AUTHOR]

Abstract: This paper addresses the possibilities of structural component models for the seismic assessment of masonry buildings using pushover analysis. The ultimate goal is to allow efficient design of new unreinforced masonry buildings in seismic areas. Different modelling strategies are presented and the implementation of a simple design tool based on structural component models is described in detail. The different approaches are applied to a two-storey building with regular plan and elevation, allowing for a comparison between them. The results indicate that macro-modelling using structural component models and pushover analysis are adequate approaches for the seismic assessment and design of unreinforced masonry buildings, as the tools require very low computational resources, allow easy interpretation of results and provide satisfactory accuracy. [Copyright &y& Elsevier]

• A novel parametric structural component, the droxel, can materialize any given structure. • The geometry of the droxels greatly simplifies the manipulation of the blocks in an automated fashion. • A controlled environment experimental campaign is presented. • The construction of parametric structures is performed efficiently via robotic operations. This manuscript presents a recently developed automated robotic system for the deployment of block-based structures. The main structural component used for the construction of the specimens is the droxel: a universal building component recently developed by the authors. The herein presented work builds on such research to create new software and hardware capabilities to deploy droxel-based structures autonomously, by means of ground robotic operations. First, the paper describes the designed mechanical components and the experimental setup. Then, the main features of the ad-hoc designed software tools will be presented, together with the salient results of the experimental campaign. Different experiments on various types of structures (e.g., shelters and bridges) constructed by means of an ABB IRB120 robotic arm will be presented and quantification of the efficiency of the operations will be discussed. Quantitative description of the stability of the structures under construction, as well as capability of deploying full scale versions of different structural system is then discussed and conclusions and recommendations drawn. [ABSTRACT FROM AUTHOR]