發(fā)布時(shí)間：2018-11-27 13:45

【摘要】：頻率法因其經(jīng)濟(jì)高效、簡便實(shí)用的特點(diǎn)在索力測量方法中占有重要地位。近幾十年來，，國內(nèi)外學(xué)者由頻率和其他結(jié)構(gòu)參數(shù)計(jì)算索力方面擬合了十幾種公式，使頻率法有很多計(jì)算選擇；但是這些公式都是確定性分析，沒有考慮頻率和結(jié)構(gòu)參數(shù)隨機(jī)性對索力結(jié)果的影響，另外在多種公式中如何選擇最優(yōu)公式，也需要分析評價(jià)。在結(jié)構(gòu)參數(shù)未知或模糊的情況下，國內(nèi)外學(xué)者從反問題的角度對關(guān)鍵參數(shù)分析識別，但幾乎都類似梯度法的方式從反向識別，對于索力測試這樣一個(gè)非線性系統(tǒng)，這樣容易使解陷入極值區(qū)間，造成解不穩(wěn)定。針對以上不足，筆者主要做了一下幾方面的工作： （1）在滿足工程實(shí)際要求的前提下，以高精度為目標(biāo)，設(shè)計(jì)一套能概率性確定索力結(jié)果和計(jì)算索力測量失效概率，對現(xiàn)存頻率法索力公式進(jìn)行精度和誤差傳遞大小評價(jià)，對索力測定中未知參數(shù)進(jìn)行正向識別的方法—神經(jīng)網(wǎng)絡(luò)-蒙特卡洛算法。該算法在擬合顯式精度、計(jì)算索力標(biāo)準(zhǔn)差和失效概率方面優(yōu)于響應(yīng)面法，又比直接有限元法節(jié)省時(shí)間。 （2）運(yùn)用算法研究了多參數(shù)的隨機(jī)性對長中短索索力結(jié)果的影響，頻率、索長、抗彎剛度、邊界條件、線質(zhì)量變異系數(shù)如果都為0.1，則長索索力結(jié)果變異系數(shù)大于0.3，短索索力結(jié)果變異系數(shù)大于0.5。對常見公式從精度和誤差傳遞大小方面進(jìn)行了評價(jià)，在兩端固結(jié)邊界條件下，任偉新、王建飛、Hiroshi Zui、邵旭東四人公式的計(jì)算結(jié)果滿足工程精度要求，應(yīng)優(yōu)先采用。 （3）基于神經(jīng)網(wǎng)絡(luò)和蒙特卡洛結(jié)合法正分析識別頻率法索力測定中的未知參數(shù)。利用多階頻率作為目標(biāo)值，全局網(wǎng)格搜索最優(yōu)解。索力及長度識別結(jié)果穩(wěn)定并且滿足工程要求精度。 （4）以南盤江懸索橋索力測量為背景，將算法應(yīng)用于工程實(shí)際，將遴選出的優(yōu)秀公式計(jì)算索力，確定索力的可靠范圍和計(jì)算測量失效概率，并且對未知參數(shù)進(jìn)行識別，最重要是索力的識別。
[Abstract]:Frequency method plays an important role in cable force measurement because of its economical, efficient, simple and practical characteristics. In recent decades, scholars at home and abroad have fitted more than ten formulas for calculating cable force by frequency and other structural parameters, which makes the frequency method have many calculation options. However, these formulas are deterministic and do not consider the influence of frequency and structural parameters randomness on cable force results. In addition, how to choose the optimal formula in many formulas also needs to be analyzed and evaluated. In the case of unknown or fuzzy structural parameters, scholars at home and abroad analyze and identify the key parameters from the point of view of inverse problems, but almost all of them are similar to the gradient method from the reverse recognition, for a nonlinear system such as cable force testing. It is easy to make the solution fall into the extremum range and cause the solution to be unstable. In view of the above shortcomings, the author mainly does some work in the following aspects: (1) under the premise of meeting the practical requirements of engineering, a set of energy probability is designed to determine the cable force result and calculate the failure probability of cable force measurement. The accuracy and error transfer size of the existing Burkina Faso force formula are evaluated, and the neural network-Monte Carlo algorithm is used to identify the unknown parameters in the determination of cable force. The algorithm is superior to the response surface method in fitting the explicit precision, calculating the standard deviation of cable force and the failure probability, and saving time compared with the direct finite element method. (2) the effect of randomness of multiple parameters on the results of cable force is studied. The frequency, cable length, bending stiffness, boundary condition and coefficient of variation of line mass are all 0.1. The coefficient of variation of long cable force and short cable force is greater than 0.3 and 0.5 respectively. The common formulas are evaluated in terms of accuracy and error transfer. Under the condition of boundary consolidation at both ends, the calculation results of Ren Weixin and Wang Jianfei, Hiroshi Zui, Shaoxu Dongsiren formula meet the requirements of engineering precision and should be adopted first. (3) based on the neural network and Monte Carlo method, the unknown parameters in the determination of Burkina Faso force are analyzed. Using multi-order frequency as the target value, the global grid search for the optimal solution. The results of cable force and length identification are stable and meet the requirements of engineering accuracy. (4) based on the measurement of cable force of the suspension bridge of Nanpanjiang River, the algorithm is applied to the engineering practice, the excellent formula is selected to calculate the cable force, the reliable range of the cable force and the failure probability of the measurement are determined, and the unknown parameters are identified. The most important is the identification of cable force.
【學(xué)位授予單位】：哈爾濱工業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：U448.25;U441

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 吳海軍,陳思甜,龔尚龍,許羿,施尚偉;斜拉橋索力測試方法研究[J];重慶交通學(xué)院學(xué)報(bào);2001年04期

2 呂大剛;賈明明;李剛;;結(jié)構(gòu)可靠度分析的均勻設(shè)計(jì)響應(yīng)面法[J];工程力學(xué);2011年07期

3 魏建東;索力測定常用公式精度分析[J];公路交通科技;2004年02期

4 程進(jìn),肖汝誠;結(jié)構(gòu)可靠度分析的混合法[J];公路交通科技;2004年07期

5 孟少平;楊睿;王景全;;一類精確考慮抗彎剛度影響的系桿拱橋索力測量新公式[J];公路交通科技;2008年06期

6 邵旭東,李國峰,李立峰;吊桿振動(dòng)分析與力的測量[J];中外公路;2004年06期

7 徐郁峰;蘇成;陳兆栓;郭奮濤;;頻率法索力測量的參數(shù)靈敏度概率分析[J];中外公路;2010年04期

8 孫江波;趙紅華;趙作周;;斜拉索索力測量方法的比較分析[J];工業(yè)建筑;2011年S1期

9 周云;易偉建;;斜拉索截面信息未知時(shí)的剛度識別及索力計(jì)算[J];湖南農(nóng)業(yè)大學(xué)學(xué)報(bào)(自然科學(xué)版);2006年04期

10 蘇成;郭奮濤;徐郁峰;;斜拉橋索力測量的可靠度研究[J];橋梁建設(shè);2009年06期

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