【摘要】：泄流誘發(fā)水工結構振動是一種復雜的流固相互作用現象,在復雜的泄流荷載作用下可能引起結構的劇烈振動,甚至破壞。碾壓混凝土結構在泄流激勵條件下結構的振動特性更加復雜,開展泄流條件下結構的振動機理及損傷識別研究,對碾壓混凝土泄流結構的設計及安全運行具有重要的指導意義。本文通過開展泄流結構水彈性模型試驗以及數值分析,結合泄流結構的流激振動特性,對碾壓混凝土分層結構的流激振動特性進行了研究,分析了水流荷載、泄流結構自身特性以及流激振動響應三者之間的關系。對應變模態(tài)與結構損傷之間的敏感性以及應變模態(tài)的正交性進行了理論分析和總結,并匯總了現有的基于應變模態(tài)的結構損傷識別指標,主要內容如下:(1)開展了一系列泄流條件下結構振動模型試驗,應用譜分析、波形分析以及時頻分析等方法對試驗數據進行分析。通過分析不同結構形式的導墻模型在泄流荷載激勵下的振動響應特征,來研究整體及分層結構在泄流條件下的隨機共振特性;(2)結合水力拍振的概念,對不同結構形式的泄流結構在不同荷載作用下開展有限元數值計算,對比分析整體與成層結構的振動響應特性,并對成層結構在泄流條件下出現的流激振動現象進行合理解釋,為高碾壓混凝土壩的設計、施工以及后期的運行管理提供依據;(3)對導墻結構進行數值模擬分析,得出整體和損傷結構應變模態(tài)的三維分布,分析了在不同損傷類型及損傷位置條件下導墻結構應變模態(tài)的變化特性;(4)針對裂縫及軟弱帶等損傷形式提出了基于應變指標的動應變時程識別方法,分別根據結構各測點動應變時程的偏態(tài)系數和均方差分布可以實現對結構損傷的準確識別;提出了光纖傳感和應變指標相結合的損傷識別方法。
[Abstract]:The vibration of hydraulic structure induced by discharge is a complex phenomenon of fluid-solid interaction, which may cause severe vibration and even destruction of the structure under complex discharge load. The vibration characteristics of RCC structure under discharge excitation are more complex. The research on vibration mechanism and damage identification of RCC structure under discharge condition is of great significance for the design and safe operation of RCC discharge structure. In this paper, through the hydroelastic model test and numerical analysis of the discharge structure, combined with the flow-induced vibration characteristics of the discharge structure, the flow-induced vibration characteristics of roller compacted concrete layered structure are studied, and the flow load is analyzed. The relationship between the characteristics of discharge structure and the response of flow-induced vibration. The sensitivity between variable mode and structural damage and the orthogonality of strain mode are analyzed and summarized theoretically, and the existing structural damage identification indexes based on strain mode are summarized. The main contents are as follows: (1) A series of structural vibration model tests under discharge conditions are carried out, and the test data are analyzed by spectral analysis, waveform analysis and time-frequency analysis. By analyzing the vibration response characteristics of guide wall models with different structural forms under discharge load, the stochastic resonance characteristics of the whole and layered structures under discharge conditions are studied. (2) combined with the concept of hydraulic beat vibration, the finite element numerical calculation of different structural forms of discharge structure under different loads is carried out, and the vibration response characteristics of the whole structure and the layered structure are compared and analyzed. The phenomenon of flow-induced vibration of layered structure under discharge condition is explained reasonably, which provides the basis for the design, construction and later operation management of high roller compacted concrete dam. (3) the numerical simulation analysis of the guide wall structure is carried out, and the three-dimensional distribution of the strain mode of the whole structure and the damage structure is obtained, and the variation characteristics of the strain mode of the guide wall structure under different damage types and damage positions are analyzed. (4) aiming at the damage forms such as cracks and weak zones, a dynamic strain time history identification method based on strain index is proposed. According to the skewness coefficient and mean square error distribution of the dynamic strain time history of each measuring point of the structure, the accurate identification of structural damage can be realized. A damage identification method based on optical fiber sensing and strain index is proposed.
【學位授予單位】：天津大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TV33

【參考文獻】

相關期刊論文 前10條

1 李桂青;馬斌;;應變模態(tài)對梁結構損傷的變化特性研究[J];低溫建筑技術;2013年03期

2 練繼建;李成業(yè);劉f ;宋明富;;環(huán)境激勵下二灘拱壩拍振機理的研究[J];振動與沖擊;2012年03期

3 李火坤;張建偉;李松輝;;基于模態(tài)應變能的水工泄流結構損傷識別研究[J];人民黃河;2012年01期

4 顧培英;鄧昌;湯雷;;基于工作應變模態(tài)損傷識別方法的試驗研究[J];振動與沖擊;2011年11期

5 張波;王峗;姜峰;;基于曲率模態(tài)差的四邊固支薄板的損傷檢測[J];河北工程大學學報(自然科學版);2009年03期

6 王永濤;臧勇;吳迪平;秦勤;范小彬;;CSP軋機扭振中“偽拍振”的研究[J];振動、測試與診斷;2009年02期

7 蘇未安;陳秀洪;;用旋轉矢量法研究“拍”現象[J];江西理工大學學報;2009年01期

8 馬斌;練繼建;楊敏;;大比尺高拱壩泄洪振動水彈性模型研究[J];中國工程科學;2008年11期

9 練繼建;李松輝;;基于支持向量機和模態(tài)參數識別的導墻結構損傷診斷研究[J];水利學報;2008年06期

10 沈文浩;張森文;李長友;曹玉華;康要強;;基于試驗模態(tài)振型的結構損傷檢測參數比較[J];暨南大學學報(自然科學版);2008年03期

，

本文編號：2479537