本文選題：土木工程　切入點：結(jié)構(gòu)健康監(jiān)測　出處：《大連理工大學(xué)》2015年博士論文

【摘要】：壓電陶瓷(如鋯鈦酸鉛,Pb-based Lanthanumdoped Zirconate Titanates,簡稱PZT)材料,因其造價低廉,以及頻率響應(yīng)范圍寬等優(yōu)點,在土木工程結(jié)構(gòu)健康監(jiān)測領(lǐng)域應(yīng)用前景廣泛。然而,盡管壓電陶瓷傳感器具有很寬的頻率響應(yīng)范圍,應(yīng)用壓電陶瓷傳感器的結(jié)構(gòu)損傷識別研究,往往只應(yīng)用到某一部分頻率范圍的傳感器信號以達(dá)到單一的監(jiān)測目的。壓電陶瓷傳感器在寬頻響應(yīng)下的動態(tài)特性及多功能監(jiān)測等方面的研究,有待進(jìn)一步發(fā)展。本文進(jìn)行了基于壓電陶瓷傳感器在300kHz內(nèi)寬頻響應(yīng)的結(jié)構(gòu)損傷識別技術(shù)研究,主要內(nèi)容如下：(1)針對粘貼式壓電陶瓷傳感器與結(jié)構(gòu)的耦合體系,提出了一種“壓電陶瓷—粘結(jié)層—被測結(jié)構(gòu)”考慮層狀介質(zhì)剪切應(yīng)變傳遞的動態(tài)力學(xué)模型。分析了驅(qū)動頻率對壓電陶瓷傳感器應(yīng)變傳遞特性的影響。并利用該模型,分別分析了壓電陶瓷片的厚度、粘結(jié)層材料、粘結(jié)層厚度對傳感器動態(tài)特性的影響,所提模型的有效性用ANSYS有限元分析和試驗加以驗證。(2)分析了寬頻激勵下,嵌入式壓電陶瓷傳感器的動態(tài)性能,提出了一種“保護(hù)層—防水層—壓電陶瓷”結(jié)構(gòu)的動態(tài)力學(xué)模型。分析了驅(qū)動頻率對壓電陶瓷極化方向動態(tài)應(yīng)力傳遞特性的影響,并分析了保護(hù)層、防水層的材料和厚度、壓電陶瓷片的厚度對傳感器動態(tài)性能的影響。利用ANSYS有限元分析和試驗驗證了分析的正確性。(3)分析了壓電陶瓷傳感器低頻響應(yīng)“拍”信號的形成機(jī)理,通過旋轉(zhuǎn)矢量法分析了結(jié)構(gòu)的阻尼效應(yīng)、荷載沖擊方向、傳感器位置對“拍”信號的影響。根據(jù)壓電陶瓷傳感器“拍”信號,提出了一種荷載沖擊方向的識別方法,并通過懸臂鋼柱的沖擊試驗驗證了方法的有效性。(4)提出了一種應(yīng)用壓電陶瓷傳感器低頻應(yīng)力響應(yīng)的結(jié)構(gòu)損傷識別方法,即基于互相關(guān)函數(shù)幅值和支持向量機(jī)的損傷識別方法,該方法僅需要壓電陶瓷傳感器測得的結(jié)構(gòu)應(yīng)力響應(yīng)信號,且適用于任意荷載激勵。利用IASC-ASCE Benchmark模型的數(shù)值驗證和桁架結(jié)構(gòu)模型的損傷識別試驗,驗證了方法的有效性。(5)基于壓電陶瓷傳感器寬頻響應(yīng)特性,提出了一種應(yīng)用壓電陶瓷傳感器低頻的結(jié)構(gòu)振動響應(yīng)信號和高頻聲發(fā)射信號的多功能監(jiān)測方法。以鋼筋混凝土梁動態(tài)彎曲破壞試驗為例,分析了壓電陶瓷傳感器在混凝土構(gòu)件中的多功能監(jiān)測；進(jìn)行了鋼筋混凝土框剪結(jié)構(gòu)模型的地震破壞監(jiān)測試驗,利用壓電陶瓷傳感器的多功能性,同時分析了結(jié)構(gòu)的動態(tài)特性和局部損傷情況。
[Abstract]:Piezoelectric ceramics (such as lead zirconate titanate Pb-based Lanthanumdoped Zirconate Titanatesfor short) are widely used in the field of civil engineering structural health monitoring due to their low cost and wide range of frequency response.However, although piezoelectric ceramic sensors have a wide frequency response range, the structural damage identification of piezoelectric ceramic sensors is often applied to a certain frequency range of sensor signals to achieve a single monitoring purpose.The dynamic characteristics and multifunctional monitoring of piezoelectric ceramic sensors in broadband response need further development.In this paper, the structure damage identification technology based on the broadband response of piezoelectric ceramic sensor in 300kHz is studied. The main contents are as follows: 1) the coupling system between the sticker piezoelectric ceramic sensor and the structure.A dynamic mechanical model considering shear strain transfer in layered media is proposed.The effect of driving frequency on the strain transfer characteristics of piezoelectric ceramic sensor is analyzed.Using this model, the effects of the thickness of piezoelectric ceramic plate, the bonding layer material and the thickness of bonding layer on the dynamic characteristics of the sensor are analyzed, respectively. The validity of the proposed model is verified by ANSYS finite element analysis and experiments.In this paper, a dynamic mechanical model of "protective layer-waterproof layer-piezoelectric ceramic" structure is proposed for the dynamic performance of embedded piezoelectric ceramic sensor.The effect of driving frequency on the dynamic stress transfer characteristics in polarization direction of piezoelectric ceramics is analyzed. The influence of the material and thickness of the protective layer, the waterproof layer and the thickness of the piezoelectric ceramic plate on the dynamic performance of the sensor is analyzed.The correctness of the analysis is verified by ANSYS finite element analysis and test. The forming mechanism of the "beat" signal of piezoelectric ceramic sensor is analyzed. The damping effect and the direction of load impact of the structure are analyzed by rotating vector method.The effect of sensor position on the "beat" signal.According to the "beat" signal of piezoelectric ceramic sensor, a method for identifying the direction of load impact is proposed.The effectiveness of the method is verified by the impact test of cantilever steel columns. (4) A structural damage identification method based on the amplitude of cross-correlation function and support vector machine is proposed, which applies the low-frequency stress response of piezoelectric ceramic sensor.This method only needs the structural stress response signal measured by piezoelectric ceramic sensor and is suitable for arbitrary load excitation.The validity of the method is verified by the numerical verification of the IASC-ASCE Benchmark model and the damage identification test of the truss structure model. The method is based on the broadband response characteristics of the piezoelectric ceramic sensor.A multifunctional monitoring method for structural vibration response signals and high frequency acoustic emission signals using piezoelectric ceramic sensors at low frequency is presented.Taking the dynamic bending failure test of reinforced concrete beam as an example, the multi-function monitoring of piezoelectric ceramic sensor in concrete member is analyzed, and the seismic failure monitoring test of reinforced concrete frame-shear structure model is carried out.The multifunctional piezoelectric ceramic sensor is used to analyze the dynamic characteristics and local damage of the structure.
【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2015
【分類號】：TU317
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本文編號：1724077