【摘要】：鐵路運輸尤其是現在高速發(fā)展的高速鐵路線路，成為了我國交通運輸最具代表性的產業(yè)，已經有許多新型的無損檢測技術廣泛使用在了尋找鋼軌的缺陷上面。研究鋼軌缺陷無損檢測的實時監(jiān)測系統(tǒng)對鐵路運輸產業(yè)的可持續(xù)性發(fā)展和安全平穩(wěn)運營是非常重要的。超聲導波在固體結構中傳播，不斷的和結構邊界相互作用，并伴隨著干涉疊加以及縱波和橫波間的模態(tài)轉換等現象，也就造成了超聲導波在彈性介質結構中通常出現多樣性的傳播模態(tài)。超聲導波在波導介質的傳播過程中，絕大多數傳播模態(tài)都具有頻率色散特性，鋼軌作為具有非常好的聲導特性的固體波導彈性介質，可以運用技術分析鋼軌中超聲導波的頻散特性來達到對應力和斷軌等諸如此類的鋼軌狀態(tài)檢測。 首先介紹了超聲導波主要是研究內容以及超聲導波無損檢測技術的四個模態(tài)特性的分析、模態(tài)的選擇、模態(tài)的控制和模態(tài)的分解部分。還從理論層面介紹了使用半解析有限元的方法可以計算得出各向同性均質自由彈性結構中超聲導波的頻散特性曲線。有限元方法的基本原理以及對于不同物理性質和數學模型的問題，還對有限元方法數學建模求解計算的基本步驟作了一定的簡單介紹。然后介紹了超聲導波無損檢測技術的情況和大致的檢測過程。然后根據彈性波在彈性介質結構中傳播的運動方程，應變位移關系和應力應變關系，計算出超聲波在無限大各向異性彈性介質結構中傳播的控制方程。同時介紹了一些彈性介質結構中的剛度矩陣的表達方程。最后簡單計算推出了超聲導波在各向同性的平板中的色散方程，還描述了超聲導波在平板中傳播的頻散曲線和導波結構。 接著提出了一種通用的方法，應用半解析有限元方法推導出在一般彈性介質結構任意截面中超聲導波的傳播模型。從過去的提出的半解析有限元方法模型中推導出在阻尼存在的粘彈性結構中，，計算求解出能量速度曲線和衰減曲線。 最后通過有限元方法對超聲導波在鋼軌中傳播模態(tài)進行了分析，對ANSYS瞬態(tài)動力學分析基本理論做了簡要描述。通過使用有限元方法首先對平板彈性介質結構中進行建模，然后擴展到對鋼軌中超聲導波傳播模態(tài)研究的有限元建模。
[Abstract]:Railway transportation, especially the high-speed railway line, has become the most representative industry in China, and many new nondestructive testing techniques have been widely used to find the defects of rail. It is very important for the sustainable development and safe and stable operation of railway transportation industry to study the real-time monitoring system of rail defect nondestructive detection. Ultrasonic guided waves propagate in solid structures, interact with structural boundaries, and are accompanied by interference superposition and modal conversion between longitudinal and shear waves. Therefore, the ultrasonic guided waves usually appear a variety of modes of propagation in elastic media structures. In the process of ultrasonic guided wave propagation in waveguide medium, most of the propagation modes have frequency dispersion characteristics. Rail is a solid waveguide elastic medium with very good acoustic conductivity. The technique can be used to analyze the dispersion characteristics of ultrasonic guided waves in the rail to detect the stress and the rail breaking. Firstly, the research content of ultrasonic guided wave and the analysis of four modal characteristics of ultrasonic guided wave nondestructive testing technology, modal selection, modal control and modal decomposition are introduced. The dispersion curves of ultrasonic guided waves in isotropic homogeneous free elastic structures can be calculated by using semi-analytical finite element method. The basic principle of the finite element method and the basic steps of solving the mathematical model of the finite element method for different physical properties and mathematical models are also briefly introduced. Then the ultrasonic guided wave nondestructive testing technology and the approximate detection process are introduced. Then the governing equations of ultrasonic wave propagation in infinite anisotropic elastic media structures are calculated according to the equations of motion strain displacement and stress-strain relations of elastic waves propagating in elastic media structures. At the same time, the expression equations of stiffness matrix in some elastic media structures are introduced. Finally, the dispersion equation of ultrasonic guided wave in isotropic plate is derived, and the dispersion curve and structure of ultrasonic guided wave propagating in the plate are also described. Then a general method is proposed, and the propagation model of ultrasonic guided waves in arbitrary sections of elastic media structures is derived by using semi-analytical finite element method. In the viscoelastic structure with damping, the energy velocity curve and the attenuation curve are calculated from the semi-analytical finite element method model proposed in the past. Finally, the mode of ultrasonic guided wave propagation in rail is analyzed by finite element method, and the basic theory of ANSYS transient dynamics analysis is briefly described. The finite element method is used to model the elastic medium structure of a flat plate, and then the finite element method is extended to the finite element modeling of the ultrasonic guided wave propagation mode in the rail.
【學位授予單位】：武漢紡織大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：U216.3;TB559

【參考文獻】

相關期刊論文 前10條

1 吳斌,王智,金山,焦敬品,何存富;用于激勵超聲導波的任意波形發(fā)生器[J];北京工業(yè)大學學報;2002年04期

2 孫繼華;韓曉華;趙洪賢;董欣;孟令華;李慶卓;黃緒萍;杜石巖;;鋼中夾雜對超聲波傳播影響的有限元模擬[J];德州學院學報;2009年02期

3 肖開豐;宋文愛;;二維有限元超聲波動方程的研究[J];國外電子測量技術;2008年05期

4 許西寧;余祖俊;朱力強;;圖解法求解Lamb波頻散方程[J];電子測量與儀器學報;2012年11期

5 馬永光,劉良玉,王璋奇,吳勃;超聲波無損檢測的計算機模擬[J];華北電力大學學報;2002年03期

6 施澤華;周海鳴;;聲彈性法及其應用[J];河海大學學報;1990年02期

7 肖開豐;宋文愛;;超聲波在各向同性固體中傳播的數值模擬[J];計算機仿真;2008年09期

8 田銘興;陳云峰;趙斌;閔永智;;實時斷軌檢測方法綜述[J];蘭州交通大學學報;2011年01期

9 劉蕊,王寅觀,陳振宇,李勇攀;利用臨界折射縱波檢測鋼軌應力[J];聲學技術;2004年04期

10 何存富;李穎;王秀彥;吳斌;李隆濤;;基于小波變換及Wigner-Ville變換方法的超聲導波信號分析[J];實驗力學;2005年04期

本文編號：2150959