發(fā)布時(shí)間：2018-03-20 16:45

  本文選題：結(jié)構(gòu)健康監(jiān)測(cè)　切入點(diǎn)：振動(dòng)測(cè)量　出處：《南京大學(xué)》2014年碩士論文　論文類型：學(xué)位論文

【摘要】：近年來,大型橋梁坍塌事故頻繁發(fā)生,導(dǎo)致巨大的生命、財(cái)產(chǎn)損失。橋梁在運(yùn)營期間自身結(jié)構(gòu)不可避免的出現(xiàn)損傷、老化的情況。在重型車輛長期作用下,內(nèi)部應(yīng)力可能嚴(yán)重受損,造成一定的交通隱患。隨著物聯(lián)網(wǎng)技術(shù)的發(fā)展,無線傳感器網(wǎng)絡(luò)技術(shù)越來越多的被應(yīng)用到橋梁結(jié)構(gòu)健康監(jiān)測(cè)中。如今越來越多的大型橋梁都配備了結(jié)構(gòu)健康監(jiān)測(cè)系統(tǒng)。其中對(duì)大部分橋梁的結(jié)構(gòu)健康監(jiān)測(cè)都包含了對(duì)其振動(dòng)狀況的監(jiān)測(cè),通過對(duì)橋梁結(jié)構(gòu)振動(dòng)信息的采集、分析來計(jì)算橋梁的振動(dòng)模態(tài),測(cè)定橋梁結(jié)構(gòu)的損傷、老化情況。 但是,橋梁結(jié)構(gòu)本身存在著振幅小、固有頻率低的特點(diǎn)。而橋梁監(jiān)測(cè)現(xiàn)場(chǎng)往往環(huán)境惡劣,不僅要經(jīng)歷天氣環(huán)境的變化,還要遭受復(fù)雜的電磁干擾。現(xiàn)有基于振動(dòng)信息采集的結(jié)構(gòu)健康監(jiān)測(cè)系統(tǒng)往往在噪聲性能上存在不足,大量橋梁振動(dòng)信息被淹沒在噪聲中,降低了數(shù)據(jù)準(zhǔn)確性,影響了最終的模態(tài)分析。此外,由于大型橋梁跨度大,由通信距離過長而帶來一系列通信質(zhì)量的問題,也降低了監(jiān)測(cè)結(jié)果的可靠性。 本文基于以往橋梁結(jié)構(gòu)健康監(jiān)測(cè)的實(shí)踐經(jīng)驗(yàn),提出并實(shí)現(xiàn)了一套應(yīng)用于橋梁結(jié)構(gòu)健康監(jiān)測(cè)領(lǐng)域的低噪聲振動(dòng)采集系統(tǒng)。從傳感器選型、采集模塊設(shè)計(jì)、電路設(shè)計(jì)、電源模塊等多角度,融入了低噪聲的設(shè)計(jì)理念。使得新的振動(dòng)采集系統(tǒng)在數(shù)據(jù)準(zhǔn)確性方面相較于以往系統(tǒng)有著顯著提升。 本文提出的振動(dòng)采集系統(tǒng),由傳感采集模塊、控制處理模塊、通信模塊和電源模塊組成。其傳感采集模塊采用了更低噪聲、更高靈敏度的加速度傳感器,提高了數(shù)據(jù)采集的準(zhǔn)確性。控制處理模塊利用了IRIS平臺(tái)強(qiáng)大的處理性能和可靠的環(huán)境適應(yīng)性。通信模塊采用的Zigbee通信協(xié)議具備功耗低,靈活性強(qiáng)的優(yōu)勢(shì),并通過通信距離擴(kuò)展器的設(shè)計(jì)延長了無線通信距離,增強(qiáng)了數(shù)據(jù)通信的可靠性。電源模塊的設(shè)計(jì)兼顧了電壓穩(wěn)定和低噪聲,保障系統(tǒng)供能穩(wěn)定、潔凈。 低噪聲振動(dòng)采集系統(tǒng)的軟件設(shè)計(jì)更多的考慮到橋梁結(jié)構(gòu)監(jiān)測(cè)的實(shí)際應(yīng)用,采用輪詢的方式進(jìn)行傳輸控制。軟件設(shè)計(jì)中考慮到在執(zhí)行監(jiān)測(cè)任務(wù)時(shí),諸多采集系統(tǒng)的時(shí)間同步。數(shù)據(jù)通信中采用確認(rèn)重傳機(jī)制來進(jìn)行差錯(cuò)控制,提高數(shù)據(jù)通信的可靠性。 通過標(biāo)準(zhǔn)振動(dòng)實(shí)驗(yàn)驗(yàn)證了系統(tǒng)對(duì)振動(dòng)測(cè)量的準(zhǔn)確性；與以往振動(dòng)采集系統(tǒng)的對(duì)比,顯示了系統(tǒng)在低噪聲性能方面較以往系統(tǒng)有著顯著提升。在橋梁現(xiàn)場(chǎng)的振動(dòng)采集實(shí)驗(yàn),采集到的數(shù)據(jù)真實(shí)有效,反應(yīng)了系統(tǒng)能夠適應(yīng)橋梁結(jié)構(gòu)健康監(jiān)測(cè)的實(shí)際應(yīng)用。
[Abstract]:In recent years, large bridge collapse accidents occur frequently, resulting in huge loss of life and property. Internal stress may be severely damaged, causing certain traffic hazards. With the development of Internet of things technology, Nowadays, more and more large bridges are equipped with structural health monitoring system. Monitoring their vibration, By collecting and analyzing the vibration information of the bridge structure, the vibration modes of the bridge are calculated, and the damage and aging of the bridge structure are measured. However, the bridge structure itself has the characteristics of small amplitude and low natural frequency. The existing structural health monitoring system based on vibration information collection often has some shortcomings in noise performance, and a large number of bridge vibration information is submerged in noise, which reduces the accuracy of data. In addition, a series of communication quality problems are brought about by the long communication distance due to the long span of large bridges, and the reliability of the monitoring results is also reduced. Based on the practical experience of bridge structure health monitoring in the past, a low noise vibration acquisition system is proposed and implemented in the field of bridge structure health monitoring, which includes sensor selection, acquisition module design, circuit design, etc. The design idea of low noise is incorporated into the power module and so on, which makes the new vibration acquisition system have a remarkable improvement in data accuracy compared with the previous system. The vibration acquisition system proposed in this paper consists of sensor acquisition module, control and processing module, communication module and power module. The sensor acquisition module adopts the acceleration sensor with lower noise and higher sensitivity. The accuracy of data acquisition is improved. The control processing module takes advantage of the powerful processing performance and reliable environment adaptability of the IRIS platform. The Zigbee communication protocol used in the communication module has the advantages of low power consumption and strong flexibility. Through the design of the communication distance extender, the wireless communication distance is extended and the reliability of the data communication is enhanced. The design of the power supply module takes into account the voltage stability and low noise, and ensures the stability and cleanliness of the power supply system. In the software design of low noise vibration acquisition system, the practical application of bridge structure monitoring is considered more and more, and transmission control is carried out by means of polling. Time synchronization of many acquisition systems. In data communication, confirmation retransmission mechanism is used to control errors and improve the reliability of data communication. The accuracy of the vibration measurement is verified by the standard vibration experiment, and compared with the previous vibration acquisition system, it is shown that the system has a remarkable improvement in low noise performance compared with the previous system. The collected data are true and effective, which reflects that the system can adapt to the practical application of bridge structure health monitoring.
【學(xué)位授予單位】：南京大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：U446

【參考文獻(xiàn)】

相關(guān)期刊論文 前8條

1 丁飛;宋光明;李建清;宋愛國;;基于ZigBee無線傳感器網(wǎng)絡(luò)的家庭控制系統(tǒng)(英文)[J];Journal of Southeast University(English Edition);2008年04期

2 朱宏平;余t，

本文編號(hào)：1639961