以參數化設計與數位製造輔助網格殼之竹構築

竹子的生長快速，3至5年即可砍伐成材，生長時間約為木材的十分之一，而且竹材為環保材料，固碳效果優異。雖然竹材具有這些優點，但是竹材應用於建築中的案例卻對於木材來的少，其原因為竹材較不易加工，並且竹材無法像木材製成規格材料，從而導致竹材較難擁有其標準化的建造流程。儘管其加工不便，無法規格化，但由於環保意識的抬頭，綠色設計(Green Design)、循環經濟與設計（Circular Economy and Design）及搖籃到搖籃（Cradle to Cradle）等的環保思維與設計結合，形成了新的設計方法，使得竹材再次復興。　　本研究以竹材作為操作對象，尋找出適合竹材的結構形式-網格殼，將竹材應用於網格殼中。研究內容主要分為四個部分：一、以參數化設計的方式進行形態找尋，於軟體中模擬其成形之形態，從中檢討竹材網格殼尺度，並透過1:10的模型進行驗證，同時測試編織網格及層疊網格的優缺點。二、竹材的試驗，分別為接點之測試、竹材長度銜接之測試與竹材彎曲之測試，並將各項小部分的測試結果統整，以此經驗實際構築出中尺度的竹片網格殼進行驗證。三、輔具製程的設計，由於竹片的寬度不一，因此透過輔具的輔助，方能加快製程時間並且提高良率，以輔具解決無法規格化的竹材所產生的加工問題。四、實際構築出兩座竹片網格殼，從中測試桿件一夾一與二夾二的差別，於設計初期使得網格殼造形產生不同的變化，包含邊緣切口的設計手法所造成的形變，以及延伸支撐的方式所創造的形態。並且設計出適合竹材構造的基礎製造方式，使竹片網格殼能具備加工快速、價格便宜與組裝快速等優勢，在任何的地方都可以在短時間內將竹片以網格殼的形式構築出一個空間。　　竹材由於無法規格化，因此於傳統建造時往往需要大量的人力，以及特殊的工法，導致竹材使用的範圍限縮。本研究以網格殼的結構形式作為操作對象，設計接點、桿件銜接方式、基礎製造及組裝方式，建構出完整的流程及方式，搭配輔具的方式提高製程效率，並於現場組裝放樣，重新思考了竹材料應用於構築中的方式及其合理性。提供竹材網格殼一個完整的作業流程及方法，成為提供給後續研究的基礎。建議後續研究者可以對於加工製程加以研究，使用不同的工具，並且以本研究所設計的輔具作為參考進行改進，使其能適用於其他的數位製造的工具，例如機械手臂銑削。或是可以往更大尺度的方向進行，使用竹稈作為桿件的研究，使竹材網格殼應用於更多方面。亦可以以此為模具，使用帆布覆蓋之後於網格殼上面敷蓋水泥，最後形成水泥薄殼。

關鍵字

竹材；網格殼結構體；參數化模型；竹構築；接點設計；輔具設計

並列摘要

Bamboo is fast-growing and is ready to cut in only three to five years, which is approximately ten times faster than timber. Moreover, as an environmentally friendly material, bamboo has a remarkable ability to fix carbon. With the advantages, however, the application of bamboo in architecture is less common than that of timber. It is because of its difficulty in manufacturing and the inability to standardize like timber. Regardless of the limitations, the bamboo tectonic has been reviving with an emergent design method that incorporates environmental perceptions such as Green Design, Circular Economy and Design, and Cradle to Cradle. This research consists of four stages that focus on the application of bamboo in gridshells, an ideal structure for bamboo. First, form-finding is performed with a parametric design that includes the simulation of form in software and the examination of grid size. The advantages and disadvantages of the fabricated and layered grid are then documented through an empirical study conducted with a series of 1:10 scale physical models. Second, the materiality of bamboo is investigated by constructing a mid-scale bamboo gridshell to attest to the feasibility based on the joint, lapping, and bending tests of bamboo strips. Third, the design of assistive devices solves the manufacturing problems caused by the unstandardized size of bamboo strips, which can accelerate the manufacturing process and reduce yield loss. Finally, evaluate the difference between the one-on-one and two-and-two bamboo strip-weaving by constructing two bamboo gridshells. The difference shapes the shell individually, including the deformation caused by the section cuts and the form induced by the extended supports. In addition, an ideal foundation for bamboo shells is designed to reduce the cost and speed up the manufacturing and assembly process, facilitating a bamboo gridshell space to be rapidly constructed everywhere. Traditional bamboo construction requires a massive workforce and unique building technologies because bamboo materials cannot be standardized, limiting the application scope of bamboo in architecture. This research centers on gridshell structures that incorporate joint design, construction of the foundation, and assembly methods. Furthermore, the research reassesses the methods and feasibility of bamboo tectonics by on-site assemblage, setting out, and assistive devices that enhance manufacturing efficiency. The study provides a comprehensive manufacturing process for bamboo gridshell that guides further research on bamboo tectonics. The researchers may concentrate on manufacturing with different tools, improving and adapting the assistive devices described in the paper to other digital fabrication tools such as CNC Machining. Moreover, researchers may focus on the bamboo structural member. The gridshell covered with tarpaulin can also serve as a mould for a concrete shell by covering cement on the surface, which expands the application scope of bamboo gridshell.