纏繞式桁架之研製

Abstract

本文目的在於使用纖維纏繞製程，研製一新型桁架結構所使用之圓桿、接頭及連接機構。研製過程除了強度考量外亦同時兼顧整體桁架組裝的便利性。文中介紹桁架製造的過程及方法，依據桁架載重需求設計圓桿之直徑、長度、纏繞角度及疊層數後再加以製作。藉由分析軟體來模擬預測圓桿受一軸向力狀況下的機械行為，再與理論計算值及實驗結果作比較驗證。其中在理論模擬上，使用有限元素法軟體-ANSYS建構有限元素模型進行分析，其抗拉強度使用兩種破壞準則來加以預測。實驗部份則是使用MTS拉伸試驗機對圓桿測定拉伸和壓縮強度。驗證結果證明理論模擬的方式可以合理的表現出圓桿的受力行為。此外接頭與連接機構之研製過程亦經多次設計改良，配合重量輕、強度高之圓桿，使得整體桁架組裝更為快速、精確及便利，為實際應用時程向前邁進一步。

The purpose of this study was to develop methods for fabricating and analyzing links, connectors, and connecting mechanism of filament wound truss structures. The production process was concerned about the strength as well as the convenience in assembling the trusses. The truss fabrication process and method began from the determination of the diameter, length, winding fiber direction, and number of layers for the links. Analytical software was used to simulate the mechanical behavior of the links under axial force. Then comparison validation was conducted on the theoretical values and actual results. For the theoretical simulation, Finite Element Method software, ANSYS, was used to construct the finite element model of the links for analysis, and two failure criteria were used to predict the tensile strength of the links. In the experiment, MTS testing machine was used to test the stretching and compressive strengths of the links. The comparison showed that the theory-based simulation when coupled with actual measurement data could predict the force endurance behavior of the links in a rational manner. The connector and connecting mechanism were improved for a number of times and when used with lightweight and high strength links, can make the assembling of the truss much faster, more accurate and convenient. The present study is a step forward to the actual application.