- 學位論文
摺疊單元應用於砌石拱頂構造模擬與數位製造之研究
Applying the Folding Unit on Simulation and Digital Fabrication of Masonry Vault
摘要
砌石拱頂是一種大跨距構造形式，由於數位模擬與數位製造流程的導入，使結構精準計算、數位放樣加工及材質開發等技術能被整合進參數軟體之中，數位技術的發展使拱頂結構突破了傳統製造上所需的時間及成本等限制，並在現今的數位時代再次被關注。由於精密計算方法的突破，產生了「結構離散化」的建造思維，這項技術被應用於複雜曲面製造，使整體構造系統能夠被分割為大量單元塊體，拱頂結構系統也迎來數位時代的全新轉譯。現行砌石拱頂離散化單元的數位製造常以三維線切割、三維銑削工藝或三維模具灌注，多使用機械手臂或客製化模具進行製造，結構模擬方法除原有非線性的結構分析軟體以外，更發展出能有效分析的推力網路分析工具。 本研究嘗試透過兩種力學模擬軟體操作與數位製造的實作相互檢驗過程，並提出一種有效的整體結構與離散化單元生成方法。首先以RhinoVault進行拱頂的找形設計，軟體基於Philippe Block所開發的Thrust Network Analysis(TNA)，以圖解方法計算壓縮的拱形樣式和網路，並在重力載荷下進行互動互易，接著參考Will Hawkins等人於2018年基於Karamba3D結構分析與實體建構的薄殼結構設計流程之研究，以研究中五優化階段測試方式，提出一套砌石拱頂構造的實作流程。 本研究利用離散化單元能夠分別加工製造、組裝、高自由度較易施工的特性，進一步發展結構橫截面調整的結構優化方式，透過參數編程及數位加工製造優化，完成拱頂構築實作。利用板材具有韌性、可彎曲並能摺疊產生結構抗性的特性，使用二維切割的摺疊系統編程製造建構成形，快速製造三維砌石拱頂構造，並以Karamba3D負重及彎曲應變能分析作為基礎，進一步檢討橫截面與整體結構的可能性。以兩種力學模擬軟體分析結果與數位製造的實作相互檢驗過程，作為擬定開發流程的基礎，並以多種拱頂形態設計反覆演繹開發流程進行實體構築驗證，最後提出一種有效的整體與單元生成方法。
並列摘要
The masonry vault is a long-span construction. In the past, it is difficult to build by traditional methods. Nowadays, due to the digital simulation and fabrication module, which is a combination of structural precision calculation and assisted lofting with digital equipment technology, and the development of material, long-span construction has surpassed the limitations of manufacturing time and cost and is attracting attention. However, in order to realize precision calculation, precision analysis, and fabricate the complex curved structure, the structural discretization method, which divides the entire structural system into a large number of units and blocks must need to be applied. These technological developments represent a significant improvement over traditional methods of thrust line analysis performed by hand, which are often tedious and time-consuming. These days, the masonry units of free-surface masonry arch are usually formed by wire cutting, CNC’s or mold lofting, and robotic arms. In addition to the existing non-linear structural analysis software, a more efficient analysis tool for Thrust Network Analysis (TNA) has been developed for structural simulation. Applying Rhino’s plug-in software Rhino Vault2 to design the shape of the vault. Based on the software Thrust Network Analysis (TNA), developed by Philippe Block, provides an intuitive graphical method for calculating compressed arched surfaces and networks, as well as interacting with each other under gravity loads. According to the research paper “Design, Construction and Testing of a Low Carbon Thin-shell Concrete Flooring System”, which was published by Will Hawkins, John Orr, and Ibell Tim, Paul Shepherd, the design process depends on the structural analysis of the grasshopper parameter design, plug-in software karamba3D, together with the physical construction of five-stage test method. Thus, the process of the masonry vault structure is developed. The above assumptions are validated by programming manufacture and solid construction using toughness, flexibility, and the ability to fold to create structural resistance. The ability of the discrete units to be disassembled, individually machined, assembled, freely editable, and easier to construct has enabled this research to further develop cross-sectional adjustment for structural optimization. Moreover, not only the development of a three-dimensional free-surface arch structure is completed by the two-dimensional cutting method, but the physical structure is also tested by karamba3D structural analysis software simulation. The validation methodology uses two types of simulation software analysis, furthermore, experiments are carried out by solid construction; besides, hardware and software parameters are also obtained to have comparison testing and discussion, and the result is used as a structural optimization scheme. Finally, the structural optimization was validated several times with different forms of the vault. The results of the research are used as a method of vault development and are effective.