臺灣博碩士論文加值系統

本文以有限元素軟體ANSYS配合實驗與彈簧模型理論等探討含側向溝槽之編織複合材料平板破壞現象。首先以彈簧模型理論計算出編織物複合材料之工程模數，再將其工程模數與實驗量測之編織物複合材料極限破壞強度代入有限元素軟體ANSYS中分析，然後得到各種不同孔洞半徑編織物複合材料平板在孔洞邊緣之應力分佈，再利用平均應力準則得到雙邊對稱半圓開孔編織複合材料之特徵長度，最後以最小平方差法建立特徵長度與孔洞半徑之函數曲線關係。實驗證實此函數可以準確地預測其他孔洞半徑之複材平板的特徵長度。

This study uses the finite element software ANSYS, experiment and the spring model theory to investigate the fracture phenomenon of braided composite plates with lateral cutout. First, we calculate the engineering moduli of braided composite plates by means of the Spring Model Method. Secondly, by the use of those calculated engineering moduli and measured fracture strengths of braided composite plates with lateral cutout, ANSYS is applied to obtain the stress distribution around the cutout of braided composite plates with different radius. And, the average stress criterion is then employed to calculate the characteristic lengths for the composite plates with different size of hole. Finally, the functional relationships between characteristic length and radius of cutout are established by the least-square method. These functions are shown to be able to accurately predict the characteristic length of other composite plate with different size of hole experimentally.

中文摘要 …………………………………………………i
英文摘要 …………………………………………………ii
目錄 …………………………………………………iii
圖目錄 …………………………………………………vi
表目錄 …………………………………………………ix


第一章 緒論……………………………………………1
1.1 前言……………………………………………1
1.2 文獻回顧………………………………………4
1.3 研究動機與目的………………………………7
1.4 本文章節提要…………………………………8

第二章 相關理論………………………………………9
2.1 特徵長度與平均應力準則(ASC) ……………9
2.2 彈簧模型………………………………………11
2.3 有限元素法……………………………………13
2.4 單位格子設定…………………………………15
2.5 單位格子之平均應變與平均應力……………17
2.5.1 平均應變………………………………………17
2.5.2 平均應力………………………………………18
2.6 彈性模數之計算………………………………22
2.7 基材模數之調整………………………………23

第三章 試片製作與拉伸實驗…………………………24
3.1 實驗材料與儀器設備…………………………24
3.2 實驗步驟與流程………………………………27
3.3 拉伸測試………………………………………30
3.4 纖維波型………………………………………34
3.5 複合材料纖維體積含有率測試………………36

第四章 有限元素軟體分析……………………………38
4.1 有限元素法與ANSYS介紹 ……………………38
4.2 分析流程與元素設定…………………………39
4.2.1 前處理…………………………………………40
4.2.2 後處理…………………………………………43

第五章 結果與討論……………………………………45
5.1 破壞模式………………………………………46
5.1.1 巨觀破壞模式…………………………………47
5.1.2 微觀破壞模式…………………………………47
5.2 應力分佈………………………………………49
5.3 孔洞半徑與特徵長度之關係…………………51

第六章 結論……………………………………………55

參考文獻 …………………………………………………56

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