光纖時域反射於碳纖管式結構健康檢測技術之研發與應用—碳纖自行車架之應用

Abstract

碳纖維由於有極高的比強度和比彈性係數、質輕等優點被廣泛使用於各領域。碳纖結構物為脆性材料，破壞前夕並無明顯塑性變形。為了使其能夠可靠及安全，最重要的是能夠即時監控損害的發生與發展。目前較少有檢測方法能夠即時監測正在使用的碳纖自行車。本研究建議使用光纖結合光時域反射的非破壞檢測方法來即時健康檢測碳纖自行車的疲勞損傷及內部缺陷。 光纖直徑小、不受電磁波干擾、耐高溫，可以內埋在碳纖複合材料中，利用光時域反射儀(OTDR，Optical Time Domain Reflection)偵測事件損失的特性來反應內部缺陷。本研究內容有關於碳纖試片、碳纖管埋設光纖的製作以及研發內埋光纖於碳纖自行車架使其能夠健康檢測的技術之過程。 在實驗室進行碳纖試片以及碳纖管內埋設光纖線，分別施作V 型與U 型撓曲試驗以及三點彎曲試驗等破壞試驗，使用OTDR 儀器量測光纖損耗量的變化，進而探討光纖結合碳纖損傷缺陷與光損失之關係，驗證其可行性。

Carbon fiber are used in various fields due to their light weight, high specific strength and specific elasticity. Carbon fiber srtuctures are brittle materials. There are no significant plastic deformations before destruction. In order to make them reliable and safe, the most important is the ability to instantly monitor the occurrence of damage and development. At present, there are less methods to be able immediately monitor the carbon fiber bicycle while the carbon fiber bicycle are in used. This study suggests that combined use of fiber optical time domain reflectometry for non-destructive testing methods to real-time health monitoring of fatigue damage in carbon fiber bike and internal defects. Optical fiber has a small diameter, is unaffected by electro-magnetic interference and is reasonably temperature resistant. It can be embedded in the carbon fiber composite material and we could use OTDR(Optical Time Domain Reflection) to detect the characteristics of the loss of internal defects. This research is about how to embed optical fiber in carbon fiber specimen with carbon fiber tube and the process to develop the carbon fiber bicycle embedded optical fiber which help healthy monitor the carbon fiber bicycle.In the laboratory, we did the experiment about V-type, U-type bending test and the three-point bending tests, which used OTDR to detect bending loss, and then discuss the relations about the light loss and carbon fiber defects further.