臺灣博碩士論文加值系統

地錨荷重計為現今量測地錨預力的主要工具，目前傳統荷重計多為電子式，但電子式感測器會因周圍電磁波干擾問題，電子迴路也易受潮損壞，而光纖光柵（Fiber Bragg Grating，FBG）具有不怕雷擊、不易受電磁波與水干擾、穩定耐用等優點，故本研究目的希望利用光纖感測優勢來研發光纖式地錨荷重計。本研究以光纖光柵受拉可提高量測範圍的概念設計了兩種機制，首先是套筒式，其優點在於能提高荷重元的解析度，但因機制以及光柵黏貼處理上較複雜導致實驗結果不如預期理想，於是設計了三環式將機制以及黏貼過程簡單化，但無法提高解析度。製作微型荷重元進行1噸的壓力測試來確認機制的可行性後，再製作全尺寸荷重計進行30噸的壓力測試，而光柵應變以及壓力的變化與理論分析是相符的，最後再進行溫度的率定並以電阻式荷重元溫度補償方式來修正溫度改變造成的影響。

Load cell has been used as a primary tool to monitor the pre-stress conditions for earth anchors. The currently used load cells are mostly electrical, the electric circuit is prone to electromagnetic interference (EMI) and humidity induced short circuit. Optical fiber Bragg grating (FBG) has the advantage of being durable and immune to lightning, EMI and humidity. This research intends to develop an FBG based load cell to take advantage of these unique capabilities. The load cell was designed so that the FBG was always subject to tensile strain to increase the range of measurement. A two layer, coaxial design was used first. However, the attachment of FBG was rather complicated, and thus this scheme was abandoned. A three layer, coaxial design was then experimented to simplify the process of attaching the FBG’s. A down sized, 1 ton capacity load cell was made to verify the design mechanism test its performance first. Afterwards, a full sized 30 ton load cell was made. The relationship between FBG readings and applied load meets the theoretical derivations. The scheme for temperature compensation in FBG load cell follows the same procedure typically used in electric load cells.

中文摘要 II
英文摘要 III
致謝 IV
目錄 V
圖目錄 VIII
第一章 緒論 1
1.1研究背景 1
1.2研究動機與目的 2
1.3研究方法 2
1.4論文架構 3
第二章 文獻回顧 5
2.1 地錨 5
2.1.1 地錨的使用 5
2.1.2地錨構造和行為機制 5
2.1.3地錨常見的破壞現象 6
2.1.3地錨荷重計於地錨上的使用 13
2.2簡易地錨量測 14
2.3光纖、光纖光柵與光纖感測器介紹 16
2.3.1光纖簡介 16
2.3.2光纖光柵感測原理 19
2.3.3光纖感測器種類及優點 22
2.4地錨荷重計 24
2.4.1電阻式荷重計 24
2.4.2振弦式荷重計 25
2.4.3光纖式荷重計 27
2.4.4承載板 29
第三章 光纖感測器設計、製作及改良 30
3.1 光纖荷重計感測原理 30
3.2套筒式荷重計 30
3.2.1設計機制與原理 30
3.2.2初始測試 32
3.2.2微型化測試及製作 36
3.3三環式荷重計 42
3.3.1設計機制與原理 42
3.3.2微型化測試 43
3.3.3全尺寸載重設計與製作 49
3.3.4全尺寸載重測試 54
3.3.5 極限承載檢驗 60
3.3.6全尺寸載重檢驗測試 63
3.3.7溫度效應補償 67
第四章 結論與建議 73
4.1測試結果討論 73
4.2結論 73
4.3建議 74
參考文獻 75

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