本文選題：自振特性　切入點(diǎn)：動(dòng)力性能　出處：《重慶交通大學(xué)》2014年碩士論文　論文類型：學(xué)位論文

【摘要】：橋梁結(jié)構(gòu)的自振特性參數(shù)是反映結(jié)構(gòu)整體工作性能的綜合性指標(biāo)，是橋梁結(jié)構(gòu)動(dòng)力分析的基礎(chǔ)，是評(píng)價(jià)橋梁動(dòng)力性能的重要依據(jù)。因此，自振特性測(cè)試分析在評(píng)價(jià)結(jié)構(gòu)性能體系中具有重要地位。然而，鑒于橋梁結(jié)構(gòu)的振動(dòng)形態(tài)的復(fù)雜性和隨機(jī)性，目前對(duì)自振特性參數(shù)的評(píng)定方法研究尚處不斷探索之中，并未形成完善的體系與統(tǒng)一的標(biāo)準(zhǔn)；在另一方面，自振參數(shù)測(cè)試結(jié)果受試驗(yàn)方法、分析參數(shù)、數(shù)據(jù)處理方法等諸多因素的影響，工程實(shí)踐中自振參數(shù)識(shí)別精度低，甚至誤判的現(xiàn)象也不少見(jiàn)。因此，對(duì)自振特性參數(shù)的測(cè)試、分析方法以及其對(duì)結(jié)構(gòu)評(píng)價(jià)方法的研究是很有必要的，本文通過(guò)理論分析，并結(jié)合現(xiàn)場(chǎng)試驗(yàn)，針對(duì)現(xiàn)有測(cè)試分析方法存在的局限性和不足，通過(guò)樣本統(tǒng)計(jì)分析、試驗(yàn)驗(yàn)證等方法，就如何提高橋梁自振特性測(cè)試方法、數(shù)據(jù)處理方法的可靠性以及如何有效地利用測(cè)得的數(shù)據(jù)來(lái)判斷結(jié)果的正確性等方面展開了系統(tǒng)的研究和分析。 本文首先指出了目前自振特性測(cè)試中存在的測(cè)點(diǎn)布置盲目性、試驗(yàn)方法缺乏針對(duì)性、參數(shù)設(shè)置不合理，，針對(duì)這些問(wèn)題作者給出自己的建議。并對(duì)自振特性測(cè)試方法的優(yōu)化進(jìn)行探討，同時(shí)以實(shí)橋?yàn)閷?duì)象，分析了測(cè)試時(shí)采樣頻率設(shè)置不當(dāng)使采集的信號(hào)失真，并對(duì)各采樣參數(shù)的設(shè)置提出了合理化建議。 其次，對(duì)自振參數(shù)測(cè)試數(shù)據(jù)處理的方法進(jìn)行探討，對(duì)于時(shí)域法本文進(jìn)行量化分析了采樣頻率的大小對(duì)實(shí)測(cè)頻率計(jì)算結(jié)果的影響，并探討了多周期平均對(duì)計(jì)算精度的改善；對(duì)于頻域法本文根據(jù)項(xiàng)目組提出的能量平均法對(duì)阻尼比的識(shí)別，進(jìn)一步提出了不同時(shí)差對(duì)計(jì)算結(jié)果的影響；同時(shí)在利用半功率點(diǎn)法識(shí)別阻尼比時(shí)，為提高頻率分辨率，統(tǒng)計(jì)了不同譜線數(shù)對(duì)分析結(jié)果的影響。 最后，本文定量分析了測(cè)試時(shí)結(jié)構(gòu)實(shí)際的剛度、頻率與理論計(jì)算的剛度、頻率之間的相互關(guān)系，提出了根據(jù)現(xiàn)場(chǎng)測(cè)得的結(jié)構(gòu)頻率，求得結(jié)構(gòu)實(shí)際剛度以及剛度的變化，對(duì)結(jié)構(gòu)性能進(jìn)行評(píng)價(jià)；分析了依據(jù)實(shí)測(cè)阻尼比對(duì)結(jié)構(gòu)性能進(jìn)行評(píng)價(jià)存在一定的可靠性，并統(tǒng)計(jì)分析了阻尼比與沖擊系數(shù)的相關(guān)性。
[Abstract]:Vibration characteristics of bridge structure is a comprehensive index reflecting the structure overall performance, is the foundation of bridge structure dynamic analysis, is an important basis for evaluating the dynamic performance of the bridge. Therefore, the self vibration characteristics analysis plays an important role in the structural performance evaluation system. However, in view of the complexity of the bridge structure and the vibration shape random, current research evaluation method of vibration characteristics is still being explored, did not form a unified and perfect system and standard; on the other hand, the vibration parameters of test results by test method, parameter analysis, effects of many factors such as the data processing method in engineering practice, self recognition precision and low vibration parameters and even misjudgment of the phenomenon is not uncommon. Therefore, the vibration characteristics test, analysis method and the structure of the evaluation method is very necessary, this paper through theoretical analysis Analysis, combined with field test, the limitations of the existing analysis methods of test and shortcomings, through statistical analysis of samples, test methods, how to improve the bridge self vibration characteristic test method, the reliability of the method of data processing and how to effectively use the measured data to judge the validity of such aspects of the research and analysis of the system.
This paper points out the current existing self vibration test in the test point arrangement test method for blindness, lack of pertinence, the parameter setting is not reasonable, aiming at these problems, the author gives his own advice. And optimization of the self vibration characteristic test method were discussed, at the same time to bridge as the object, analyzed the test set sampling frequency improper acquisition signal distortion, and puts forward reasonable suggestions for the parameters of each sampling set.
Secondly, to discuss the vibration parameter test data processing method, this paper makes a quantitative analysis of time domain method for the effect of sampling frequency on the size of the measured frequency calculation results, and discusses the multiple period average on the calculation accuracy is improved; for the frequency domain method according to the project team's average energy method to identify the damping ratio. Put forward different time effect on the results; at the same time using the half power point method to identify damping ratio, in order to improve the frequency resolution, the statistics of different lines of influence on the analysis results.
At last, this paper quantitatively analyzes the test of actual structure stiffness, frequency and stiffness calculation theory, the relationship between frequency, frequency is proposed according to the structure of the site measured, calculated structure stiffness and the actual stiffness changes, to evaluate the structure performance; analyzed based on the measured damping ratio on the performance of there is a certain reliability evaluation, and statistical analysis of the correlation between damping ratio and impact factor.

【學(xué)位授予單位】：重慶交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：U441.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前3條

1 江阿蘭;;基于橋梁結(jié)構(gòu)動(dòng)力特性損傷識(shí)別方法的研究[J];林業(yè)科技情報(bào);2005年04期

2 劉雨青,吳代華,李卓球,宋顯輝;基于環(huán)境振動(dòng)測(cè)試的橋梁動(dòng)力特性[J];武漢理工大學(xué)學(xué)報(bào);2005年11期

3 續(xù)秀忠,華宏星,陳兆能;基于環(huán)境激勵(lì)的模態(tài)參數(shù)辨識(shí)方法綜述[J];振動(dòng)與沖擊;2002年03期

本文編號(hào)：1626263