International Journal of Space Structures最新文献

{"title":"Geometric analysis of the MDF kerf-bending structure accuracy","authors":"Barbara Ruschel Lorenzoni, F. P. D. Silva","doi":"10.1177/09560599221081015","DOIUrl":"https://doi.org/10.1177/09560599221081015","url":null,"abstract":"In digital design, rigid flat materials commonly hinder the fabrication of complex-curved geometries. A fabrication approach based on the socalled bending cut patterns or “kerf-bending” can be used to improve the ability of a material to bend. This bending method relies on a complex mechanical behavior, requiring an accurate evaluation of the resultant surface. By mastering the geometric effects, some adjustments can be made to the project so that the result better approximates the designer’s intentions. This study focused on geometric accuracy of MDF kerfbending, including target-geometry design, cutting, bending, 3D scanning and analysis. It demonstrated that depending on the arc bending radius, the sample with a defined cut pattern may become excessively tensioned, protruding to the outside, or without enough stiffness to conform to an ideal shape. Experiments have validated this methodology and obtained a stable and precise half-cylinder by selecting the most adequate radius range for the material and parameters adopted.","PeriodicalId":34964,"journal":{"name":"International Journal of Space Structures","volume":"37 1","pages":"135 - 149"},"PeriodicalIF":0.0,"publicationDate":"2022-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41453017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to BIM based decision-support tool for automating design to fabrication process of freeform lattice space structure","authors":"Saeid Haghir, Ramtin Haghnazar, Sara Saghafi Moghaddam, Dan Keramat, M. Matini","doi":"10.1177/09560599221089050","DOIUrl":"https://doi.org/10.1177/09560599221089050","url":null,"abstract":"","PeriodicalId":34964,"journal":{"name":"International Journal of Space Structures","volume":"37 1","pages":"168 - 168"},"PeriodicalIF":0.0,"publicationDate":"2022-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45289896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grid-shell design and analysis via reciprocal discrete Airy stress functions","authors":"M. Konstantatou, W. Baker, Timothy Nugent, A. McRobie","doi":"10.1177/09560599221081004","DOIUrl":"https://doi.org/10.1177/09560599221081004","url":null,"abstract":"This research paper introduces a theoretical framework for the design and analysis of compression-and-tension grid-shells in static equilibrium where the states of self-stress function as design freedoms. This is based on a synthesis of reciprocal discrete Airy stress functions in the context of graphic statics and the Force Density Method (FDM). Specifically, the former is a direct method for generating 2-dimensional global static equilibrium whereas the latter allows for its 3-dimensional implementation. As a result, creative design explorations can take place directly within the equilibrium space without the need for iterative convergence algorithms to obtain equilibrium. The use of reciprocal Airy stress functions in conjunction with the lower bound theorem gives insight and explicit control with regards to the states of self-stress as design and analysis freedoms which can define the structural form and its load path.","PeriodicalId":34964,"journal":{"name":"International Journal of Space Structures","volume":"37 1","pages":"150 - 164"},"PeriodicalIF":0.0,"publicationDate":"2022-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45604272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design based on availability: Generative design and robotic fabrication workflow for non-standardized sheet metal with variable properties","authors":"Seyed Mobin Moussavi, Hana Svatoš-Ražnjević, A. Körner, Y. Tahouni, A. Menges, J. Knippers","doi":"10.1177/09560599221081104","DOIUrl":"https://doi.org/10.1177/09560599221081104","url":null,"abstract":"This paper presents the use of a computational design algorithm in combination with robotic fabrication and sensing to augment the design and construction process for non-standardized material. Although reusing reclaimed material can significantly reduce the environmental impact in building construction, current design processes are not set up for this shift in thinking. Contrary to conventional practices, designing within the constraints of available material means that geometry and topology cannot be fully pre-determined. This paper introduces a design methodology for corrugated shell structures from folded sheet metal of variable geometries and properties, in which the design goal adapts to available material. It follows a two-fold approach of digital algorithm development and scanning and physical prototyping for robotic fabrication. The scanned materials database is classified based on object geometry data and material properties; such as thickness, type of metal, and spring-back values for fabrication purposes. Together with a target surface, it is an input for a generative design algorithm consisting of surface generation and optimization. The surface generation tries to approximate the target through a translation of search algorithm results for object placement into a 2D mesh graph which is then linked to 3D particle spring based form-finding. The optimization consists of evaluation of structural, fabrication, and design criteria, with finally user selection. Robotic fabrication included object recognition, metal sheet folding and consideration of different metal spring back behavior. These methods were tested on a single curved arch surface and applied to a double curved cantilever canopy as a final demonstrator. The algorithm results showed a generation of different corrugated shell topologies based on iterated object placement. As a demonstrator, a part of the selected canopy was robotically fabricated from local industrial leftovers.","PeriodicalId":34964,"journal":{"name":"International Journal of Space Structures","volume":"37 1","pages":"119 - 134"},"PeriodicalIF":0.0,"publicationDate":"2022-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48483942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial Structures 2020/21 Conference Report","authors":"S. Behnejad, P. Wicks","doi":"10.1177/09560599221076476","DOIUrl":"https://doi.org/10.1177/09560599221076476","url":null,"abstract":"The International Conference on Spatial Structures has been organised and held on five previous occasions by the Spatial Structures Research Centre of the University of Surrey in 1966, 1975, 1984, 1993 and 2002, and in 2011 in collaboration with the International Association for Bridge and Structural Engineering (IABSE) and International Association for Shell and Spatial Structures (IASS). The seventh conference was hosted by the University of Surrey from the UK during 23rd – 27th August 2021; it was combined with the 2020 annual symposium of the IASS. The conference was named IASS 2020/21 – Surrey 7 and its strapline was “Inspiring the next generation”. The planning and delivery of the conference had a long history: beginning in January 2016, and latterly very heavily affected by the worldwide Covid 19 pandemic emerging during late 2019/early 2020. The original planned dates were 24th – 28th August 2020, but as the impact of the pandemic became more profound, the mode of delivery evolved from fully in-person (designated as S0 mode of delivery), through hybrid in-person/virtual (S1) to eventually becoming fully virtual (S2) throughout the revised dates during August 2021. Under these circumstances, achievement required a highly professional, flexible, and agile Executive Group (EG) planning for and working on an entirely novel delivery model. The team was partly drawn from the conference corporate Organising, Scientific and Industrial Committees and comprised representatives from the Surrey University Department of Civil and Environmental Engineering, Procurement, Events team, Faculty and Research Communications and Marketing teams; along with outside contractors providing wider support and specialist technical services. The internationalism of the conference participants (see Figure 1) and the virtual delivery model presented the EG with unique challenges. Spatial Structures 2020/21 Conference Report","PeriodicalId":34964,"journal":{"name":"International Journal of Space Structures","volume":"37 1","pages":"65 - 78"},"PeriodicalIF":0.0,"publicationDate":"2022-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49328697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The experimental study on the vibration of membrane structure under impact load","authors":"Ping Liu, Xinkun Yang, Dan Li","doi":"10.1177/09560599211064111","DOIUrl":"https://doi.org/10.1177/09560599211064111","url":null,"abstract":"The present paper investigated the characteristic of the vibration of a membrane structure under impact load based on a series of experiments. Eight cases with different pretension forces by varying the pretension load in the lateral direction were carried out. The impact loads were applied on the center position of the membrane. The results of frequency, vibration amplitude, and damping ratio were discussed. It is shown that there is a main vibration mode with different main frequencies in the vibrations and the duration is the same under the different impact loads. The frequency is linear to the pretension force, and the amplitude of the vibration decreases by an exponential function determined by the parameter of the damping ratio. When the pretension force exceeded a threshold (6.2% of strength), the maximum amplitude and vibration duration tend to be a fixed value.","PeriodicalId":34964,"journal":{"name":"International Journal of Space Structures","volume":"37 1","pages":"107 - 118"},"PeriodicalIF":0.0,"publicationDate":"2022-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46715748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of tension structures and shells using the Airy stress function","authors":"Alexander Sehlström, K. Olsson, Chris J. K. Williams","doi":"10.1177/09560599211064104","DOIUrl":"https://doi.org/10.1177/09560599211064104","url":null,"abstract":"Discontinuities in the Airy stress function for in-plane stress analysis represent forces and moments in connected one-dimensional elements. We expand this representation to curved membrane-action structures, such as shells and cable nets, and graphically visualise the internal stresses and section forces at the boundary necessary for equilibrium. The approach enhances understanding of the interplay between form and forces and can support design decisions related to form-finding and force efficiency. As illustrative examples, the prestressing needed for three existing cable nets is determined, and its influence on the edge-beam bending moment is explored.","PeriodicalId":34964,"journal":{"name":"International Journal of Space Structures","volume":"37 1","pages":"94 - 106"},"PeriodicalIF":0.0,"publicationDate":"2021-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45434278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of tape flexures for space borne deployable structures","authors":"Hemant Arora, R. Dangarwala, S. Mukherjee, Bhavdeep Singh Munjal","doi":"10.1177/09560599211064096","DOIUrl":"https://doi.org/10.1177/09560599211064096","url":null,"abstract":"Space exploration arises the demand for launching large size structures to satisfy the need of high bandwidth telecommunication, earth observation and deep space interplanetary missions. Launching of these monolithic structures of sizes 3 m or more are not feasible due to limited launch fairing space of state-of-the-art launch vehicles. Therefore, the development of innovative deployment mechanisms is need of the hour. Deployment process of space borne deployable systems is the process of transition from mechanism to structure which is one of the unreliable stage due to existence of many conventional rotary joints which causes loss of energy due to backlash, friction and misalignment. An investigation study is presented in this paper for churning out a solution of flexible hinges using tape springs in state-of-the-art space deployable configurations which eliminates the factors causing loss of energy. Analytical and experimental methods are evaluated for investigating the bending behaviour of tape flexures. Tape flexures demonstrate to be a suitable candidate for compliant deployable configuration. The proposed configuration with combination of two tape flexures mounted in such a way that concave curve of each tape faces each other are structurally analysed for desired rotation angle. A comparison study is carried out for various material options of single and double layered tape flexures proposed for a flexure hinge. Practical feasibility of the proposed configuration is also demonstrated successfully on space borne deployable structures.","PeriodicalId":34964,"journal":{"name":"International Journal of Space Structures","volume":"37 1","pages":"37 - 48"},"PeriodicalIF":0.0,"publicationDate":"2021-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43371433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bias deployable grids with horizontal compound scissor-like elements: A geometric study of the folding/deployment process","authors":"M. Freire-Tellado, M. Muñoz-Vidal, J. Pérez-Valcárcel","doi":"10.1177/09560599211064094","DOIUrl":"https://doi.org/10.1177/09560599211064094","url":null,"abstract":"Bias deployable structural units are two-way structures arranged in a rotational pattern with respect to the edges. They have interesting advantages such as robust three-dimensional operation with supports around their entire base perimeter and the exclusive use of load-bearing scissor-like elements (SLEs). However, they do not have edge trims and their resistance to angular distortion is limited. This article proposes a series of deployable bi-stable structures that address these problems and incorporate new, resilient features. A method of analysing the incompatibilities of the structural unit is developed based solely on the geometric study of the deployment process, which allows the level of incompatibility of the proposal to be graduated, varying from stress-free structures to bi-stable structures. A kinematic model of one of the proposals allows the research undertaken to be contrasted.","PeriodicalId":34964,"journal":{"name":"International Journal of Space Structures","volume":"37 1","pages":"22 - 36"},"PeriodicalIF":0.0,"publicationDate":"2021-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44861334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The optimization process leading to the tessellation of the first geodesic dome structure, the first Planetarium of Jena","authors":"O. Gáspár","doi":"10.1177/09560599211064110","DOIUrl":"https://doi.org/10.1177/09560599211064110","url":null,"abstract":"The tessellation of the first built geodesic dome structure (the first planetarium of Jena, designed by Walther Bauersfeld, built 1922–23) has been unknown until recently. While original documentation of the tessellation has been published, the concept behind it has not been uncovered. This article presents the evolution of the final tessellation based on Bauersfeld’s hand-written notes found in the Zeiss Archives in Jena. Bauersfeld contemplated various methods of subdivision and performed detailed calculations and optimality analysis on them—preceding the theoretical studies on the tessellation of geodesic domes by almost 30 years. His key findings, relevant and comparable with later studies are highlighted. The concept of the presumably final tessellation is revealed to be the equal-area triangulation of the sphere—which has to the author’s knowledge not been considered ever since for geodesic domes. The remarkably simple algorithm applied did not result in a theoretically exact solution (well known to Bauersfeld), but as shown in this article in engineering terms it got sufficiently close. Moreover, it is concluded that the resulting tessellation excels in terms of important parameters (e.g. edge length ratio, number of different edges) compared to existing practical and theoretical solutions.","PeriodicalId":34964,"journal":{"name":"International Journal of Space Structures","volume":"37 1","pages":"49 - 64"},"PeriodicalIF":0.0,"publicationDate":"2021-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44879179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}