本文選題：地基微波干涉雷達 + IBIS系統(tǒng)�。� 參考：《北京建筑大學(xué)》2017年碩士論文

【摘要】：地基微波干涉雷達集成步進頻率連續(xù)波技術(shù)、合成孔徑雷達技術(shù)和干涉測量技術(shù),采用非接觸式的測量方式,獲取實時的動態(tài)監(jiān)測數(shù)據(jù),成為變形監(jiān)測領(lǐng)域一種新型監(jiān)測技術(shù)。本文基于意大利IDS公司生產(chǎn)的地基干涉雷達IBIS系統(tǒng)展開相關(guān)研究工作,進行了系統(tǒng)綜合性能測試、希爾伯特-黃變換理論研究及其在地基雷達數(shù)據(jù)處理中的應(yīng)用研究。主要內(nèi)容如下:1、IBIS系統(tǒng)綜合性能測試。利用角反射器與螺旋測微器的組合裝置模擬變形,檢測IBIS系統(tǒng)測量精度,結(jié)果表明其精度優(yōu)于亞毫米級。為保證IBIS系統(tǒng)監(jiān)測精度,進一步研究儀器安置誤差和大氣因素誤差的影響,利用實驗與數(shù)據(jù)模擬的方法證明安置儀器時仰角、距離對觀測精度的影響,并通過采集的氣象數(shù)據(jù),證明大氣因素對觀測結(jié)果存在影響,需要應(yīng)用大氣參數(shù)模型對觀測結(jié)果進行改正。2、IBIS系統(tǒng)動態(tài)監(jiān)測應(yīng)用。采用IBIS系統(tǒng)對某高速鐵路橋梁進行了形變動態(tài)測量研究,對簡支箱梁、大跨度的連續(xù)現(xiàn)澆梁、橋墩及聲屏障等橋梁關(guān)鍵結(jié)構(gòu)進行多期的測量,獲得了測量對象的動態(tài)位移序列。此外,應(yīng)用IBIS系統(tǒng)完成了通州燃燈古塔的監(jiān)測項目,設(shè)計了對高聳建筑的監(jiān)測方案和數(shù)據(jù)處理方法。結(jié)合橋梁監(jiān)動態(tài)監(jiān)測方案總結(jié)了完整的IBIS動態(tài)監(jiān)測體系。3、基于希爾伯特—黃變換(HHT)理論,針對地基雷達IBIS系統(tǒng)所獲取的非線性、非穩(wěn)態(tài)的振動信號,進行了分析研究:(1)經(jīng)驗?zāi)B(tài)分解(EMD)振動信號重構(gòu)。針對動態(tài)測量結(jié)果受到高頻噪聲的影響,采用具有自適應(yīng)性信號處理方法EMD對地基雷達原始信號進行降噪處理。將原始信號分解為由高頻至低頻的一系列本征模態(tài)函數(shù)(IMF),利用相關(guān)系數(shù)判定噪聲界限,將各IMF重構(gòu)成為噪聲序列、周期序列和趨勢序列。與原始信號相比,重構(gòu)的周期序列可以更精確反映建筑物的振動細節(jié)和周期變化。(2)HHT模態(tài)參數(shù)識別。為獲得高速鐵路橋梁在列車激勵作用下的有載頻率,應(yīng)用HHT理論將原始信號分解為表示振動響應(yīng)的本征模態(tài)函數(shù)(IMF),通過Fourier頻譜圖考察振動響應(yīng)的主模態(tài),利用隨機減量技術(shù)(RDT),提取主模態(tài)振動響應(yīng)中的確定性信號并進行Hilbert變換,進而識別在激勵作用下建筑物振動的固有頻率。在地基雷達數(shù)據(jù)處理過程中,與HHT理論進行有機結(jié)合,可以有效的剔除噪聲影響,獲取真實的位移數(shù)據(jù),精確識別建筑物模態(tài)參數(shù),為建筑物的健康評估提供科學(xué)、準確的依據(jù),從而證明了將HHT理論應(yīng)用于處理地基雷達數(shù)據(jù)具有良好的適用性。
[Abstract]:The ground-based microwave interferometric radar integrated step frequency continuous wave technology, synthetic aperture radar technology and interferometric measurement technology, using non-contact measurement method to obtain real-time dynamic monitoring data, become a new monitoring technology in the field of deformation monitoring.Based on the IBIS system of ground interference radar produced by IDS company in Italy, the comprehensive performance of the system is tested, and the theory of Hilbert-Huang transform and its application in ground radar data processing are studied in this paper.The main contents are as follows: 1: 1 IBIS system comprehensive performance test.The combined device of angle reflector and spiral micrometer is used to simulate the deformation to detect the measuring accuracy of IBIS system. The results show that the accuracy of the system is superior to that of sub-millimeter.In order to ensure the monitoring accuracy of IBIS system and further study the influence of instrument placement error and atmospheric factor error, the influence of elevation angle and distance on the observation accuracy is proved by means of experiment and data simulation, and the meteorological data are collected.It is proved that the atmospheric factors have influence on the observed results, and the atmospheric parameter model should be used to correct the observed results.The deformation dynamic measurement of a high-speed railway bridge is studied by using IBIS system. The dynamic displacement sequence of the measuring object is obtained by measuring the key structures of the bridge, such as simply supported box girder, long-span continuous cast-in-situ beam, piers and sound barrier, etc.In addition, the IBIS system is used to complete the monitoring project of the ancient tower of Tongzhou fuel lamp, and the monitoring scheme and data processing method of the towering building are designed.Based on Hilbert-Huang transform (HHT) theory, this paper sums up the complete dynamic monitoring system of IBIS combined with the dynamic monitoring scheme of bridge supervision, aiming at the nonlinear and unsteady vibration signals obtained by the IBIS system of ground-based radar.In this paper, the reconstruction of EMD-1 vibration signal by empirical mode decomposition (EMD) is studied.In view of the effect of high frequency noise on the dynamic measurement results, the adaptive signal processing method (EMD) is adopted to reduce the noise of the original signal of ground-based radar.The original signal is decomposed into a series of intrinsic mode functions from high frequency to low frequency. The correlation coefficient is used to determine the noise limit and the IMF is reconstructed into noise sequence, periodic sequence and trend sequence.Compared with the original signal, the reconstructed periodic sequence can more accurately reflect the vibration details of the building and the periodic variation.In order to obtain the loaded frequency of high-speed railway bridge under train excitation, the original signal is decomposed into the intrinsic mode function of vibration response by using HHT theory, and the main mode of vibration response is investigated by Fourier spectrum diagram.By using random decrement technique, deterministic signals are extracted from the vibration response of the main mode and Hilbert transform is carried out to identify the natural frequencies of the vibration of buildings under excitation.In the process of ground radar data processing, combining with HHT theory, it can effectively eliminate the influence of noise, obtain real displacement data, identify the modal parameters of buildings accurately, and provide a scientific method for building health assessment.It is proved that the application of HHT theory to ground-based radar data processing has good applicability.
【學(xué)位授予單位】：北京建筑大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：U446

【參考文獻】

相關(guān)期刊論文 前10條

1 鄒進貴;田徑;陳艷華;毛慶華;李琴;;地基SAR與三維激光掃描數(shù)據(jù)融合方法研究[J];測繪地理信息;2015年03期

2 賈瑞生;趙同彬;孫紅梅;閆相宏;;基于經(jīng)驗?zāi)B(tài)分解及獨立成分分析的微震信號降噪方法[J];地球物理學(xué)報;2015年03期

3 董杰;董妍;;基于氣象數(shù)據(jù)的地基雷達大氣擾動校正方法研究[J];測繪工程;2014年10期

4 張恒t，

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