仿生結構中，蜂巢結構是最常見並且也大量使用在日常生活中，大部分蜂巢結構的研究在載重形式上通常只給定單一比例載重，但實際結構在使用的狀態，可能遭受到反覆的載重，甚至多向的負載，因此只考慮單軸載重對結構的影響並不全面；再者，多數的蜂巢結構研究，只探討單軸單調載重下的彈性行為或韌性，較少針對塑性範圍的探討。因此，本文針對蜂巢結構在循環與多個軸向的加載下，其力學現象，特別是塑性行為的探討。本文以有限元素法模擬不同方向性的梁狀與板狀蜂巢結構，並就整體的力學性能與局部的應力分佈進行討論。在整體的力學性能方面，我們在蜂巢結構進行軸向與橫向循環加載，探討的能量吸收效果，觀察得知，軸向加載有較佳的能量吸收效果，且具有抗剪力的效果。在多軸加載方面，我們對蜂巢結構進行結構降伏點刺探的模擬實驗，對結構施加各個方向的位移，並將降伏點連線繪製成降伏面，藉此來找出結構的彈性範圍；不僅如此，我們更進一步對蜂巢結構進行預加載，再探測蜂巢結構在不同加載路徑後的接續降伏面。因此，得出蜂巢結構在使用過後，其彈性範圍會增加並往特定方向移動。最後，我們觀察蜂巢結構的應力場，期望能找出改變應力分佈的方式，因此提出一種加入軟材的方式，透過改變局部蜂巢結構的材料，觀察結構應力分佈的變化與整體能量吸收能力，並由模擬結果得出，在相同硬材面積的情況下，透過連續佈置軟材的方式有助於改變應力分佈與硬材單位面積下的能量吸收能力。

Honeycombs is the most common bio-inspire structure and it is widely used in industry. To understand the behavior of honeycombs, many investigations have been conducted. Among the investigation, the proportional loading is the major consideration. However, the structure may be subjected to cyclic and/or multi-directional loadings during service. Furthermore, in the investigation, the elastic behavior of honeycombs as well as the toughness have been discussed but their plastic behavior has not been explored systematically. Therefore, we investigated the mechanical phenomena of honeycombs beyond the elastic range under cyclic and multi-directional loading in this study. Two different types of honeycombs, including beam-like and plate-like structures with different orientation were designed and FEM simulations were conducted. We applied cyclic loadings in the longitudinal and latitudinal directions to honeycombs for the observation of the energy absorption capacity. Simulations showed that honeycombs have better energy absorption ability and shear resistance performance under longitudinal loading. In terms of multi-directional loadings, we numerically probed the yield point of honeycombs in the load space under the displacement control and then constructed initial yield surfaces. In addition, we applied pre-loading path to honeycombs and then detected subsequent yield surfaces. The evolution of yield surface of honeycombs from initial state was observed and shows that the elastic range of honeycombs moves and deforms and its area increase during the loading. Furthermore, we observed the stress field of honeycombs and proposed a way to replace the part of structure as soft material. This replacement changes the local stress distribution and the global energy absorption capacity of honeycombs.

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