本文選題：光柵傳感 + 現場工況　； 參考：《西南交通大學》2017年碩士論文

【摘要】：無縫鋼軌以其獨有的優勢得到世界各國鐵路部門的青睞,同時無縫線路的健康狀態也成為人們研究的焦點。光纖光柵傳感技術擁有高測量精度、體積小等諸多優點正成為軌道安全監測的新型應用。通過光纖光柵反射回來的波長信息進行相應數據處理可以推算出軌道的運行狀態,對線路的運營安全做出指導性參考。在本文中,光纖布拉格光柵(Fiber Bragg Grating)傳感技術將被應用于軌道健康監測系統中,針對不同無縫線路工況推導出不同的光纖光柵傳感特性,繼而結合現場不同工況下光纖光柵傳感特性提出了一套鐵路附加力測量的方案。本文首先對無縫線路研究背景和目的做了簡介,并將國內外鋼軌縱向附加力研究方法做了總結,針對附加力測量中存在的問題引出本文主要工作和結構安排。之后介紹光纖光柵溫度及應變傳感特性,同時對光纖光柵在應用中常見的溫度和應變同時交叉影響問題做了解決方法歸納,最后為了能將光纖光柵應用于惡劣測量環境中,對光纖光柵封裝工藝做了部分研究。其次模擬鐵路現場工況,即鋼軌豎向及軸向分別處于自由以及受約束的受力狀態,探究在這兩種條件下的光纖光柵傳感原理并加以實驗驗證,實驗結果表明在軌溫變化60℃范圍內,FBG_1與FBG_2傳感特性的理論推導值與實際測量之間的誤差分別為1.6%和3.2%。通過對不同約束條件光纖光柵傳感特性的驗證不僅可標定出光纖光柵的應變以及溫度靈敏度系數,同時可以為無縫線路縱向力有效測量提供更多的理論依據。最后介紹鐵路無縫線路鋼軌固定區附加力測量困難的原因,針對此困難提出一種用于測量附加力的新型光纖光柵結構一異構光纖光柵傳感器,并對異構光纖光柵傳感器測量鋼軌附加力做了原理推導,通過實驗驗證異構光柵相對波長差與縱向附加力具有高于0.999的線性度,且通過異構光柵測量得縱向附加力與理論值的誤差在5%以內。異構光柵不僅可以解決自身溫度補償問題,同時溫度變化導致的無縫線路應變監測困難也可得到有效解決,之后結合之前設計的封裝工藝來進行異構光柵封裝保護,并對封裝后的異構光柵進行附加力的測量,其中使用封裝后異構光柵傳感器測量附加力精度可達92.5%。
[Abstract]:Because of its unique advantages, the seamless rail has been favored by the railway departments all over the world, and the health status of the seamless rail has also become the focus of research. Fiber Bragg grating (FBG) sensing technology has many advantages, such as high measurement precision and small size, which is becoming a new application of track safety monitoring. Through the corresponding data processing of the wavelength information reflected from the fiber grating, the operating state of the track can be calculated, and the guiding reference for the operation safety of the line can be made. In this paper, fiber Bragg grating sensing technology will be applied to track health monitoring system. Then, according to the sensing characteristics of fiber Bragg grating (FBG) in different working conditions, a set of railway additional force measurement scheme is proposed. In this paper, the background and purpose of the research on CWR are introduced, and the research methods of longitudinal additional force of rail are summarized, and the main work and structure arrangement of this paper are brought forward in view of the problems existing in the measurement of additional force. Then, the temperature and strain sensing characteristics of fiber grating are introduced, and the common cross-effects of temperature and strain in the application of fiber grating are summarized. Finally, in order to be able to apply fiber Bragg grating in harsh measurement environment, The packaging technology of fiber grating is studied in part. Secondly, the paper simulates the working condition of railway field, that is, the vertical and axial direction of rail are in the free and constrained state respectively. The principle of fiber Bragg grating sensing under these two conditions is explored and verified by experiments. The experimental results show that the errors between the theoretical derivation of the sensing characteristics of FBG-1 and FBG_2 and the actual measurements are 1.6% and 3.2% respectively in the range of 60 鈩，

本文編號：1917731