本文選題：結(jié)構(gòu)識別 + 模態(tài)柔度�。� 參考：《湖南大學(xué)》2015年碩士論文

【摘要】：鋼-混凝土組合結(jié)構(gòu)是橋梁結(jié)構(gòu)中的一種常見形式,對其進(jìn)行結(jié)構(gòu)識別研究有著重要的意義。本文在總結(jié)之前研究成果的基礎(chǔ)上,對一塊實驗室鋼-混凝土組合橋面板和一座鋼-混凝土組合結(jié)構(gòu)橋梁進(jìn)行靜動載試驗及子結(jié)構(gòu)模態(tài)柔度識別研究。具體研究內(nèi)容如下:(1)在理論上總結(jié)了兩種模態(tài)柔度計算方法,提出兩種模態(tài)識別方法在本質(zhì)上進(jìn)行模態(tài)柔度的求解是一致的。利用兩種方法相互轉(zhuǎn)化的特點,可以得到結(jié)構(gòu)的質(zhì)量歸一振型。同時,提出了利用分片測試獲取結(jié)構(gòu)整體模態(tài)柔度的理論。其過程是對子結(jié)構(gòu)質(zhì)量歸一振型進(jìn)行拼接得到擴充的整體振型,再利用拼接的振型計算結(jié)構(gòu)的整體柔度矩陣。(2)對一混凝土板有限元模型和一實驗室鋼-混凝土組合板進(jìn)行脈沖錘擊測試實驗,表明單點輸入單點輸出(SISO),單點輸入多點輸出(SIMO)和多點輸入多點輸出(MIMO)等方法均能較為準(zhǔn)確地獲取模態(tài)柔度系數(shù),并能通過子結(jié)構(gòu)振型拼接的方法獲得與靜力方法相差很小的模態(tài)柔度矩陣。通過對一座實際橋梁的脈沖錘擊法分片測試,驗證了該方法在實際運用的可行性。同時,進(jìn)行了隨機振動測試下的振型質(zhì)量歸一研究。通過有限元數(shù)值試驗和實驗室的隨機振動試驗表明,基于集中質(zhì)量矩陣假設(shè),可以利用隨機振動測試獲取結(jié)構(gòu)的模態(tài)柔度,其結(jié)果比實際結(jié)構(gòu)要柔。(3)基于模態(tài)柔度方法進(jìn)行結(jié)構(gòu)損傷識別研究。首先,設(shè)計了支座剛度變化、連接件損傷和橫向支撐破壞這三種損傷工況用來模擬實際橋梁結(jié)構(gòu)可能出現(xiàn)的損傷狀況。通過對比結(jié)構(gòu)損傷前后的模態(tài)柔度位移信息,成功實現(xiàn)了組合板的損傷識別。結(jié)果表明模態(tài)柔度是極好的損傷指標(biāo),其對損傷的敏感程度比頻率和振型大得多。其次,通過靜力加載造成試驗板的靜力損傷,并利用模態(tài)柔度方法成功地識別出靜力損傷的位置和損傷程度。(4)基于Strand7有限元軟件和Mat lab應(yīng)用程序的API交互訪問技術(shù)對鋼-混凝土組合板結(jié)構(gòu)進(jìn)行有限元模型修正。首先,比較了三種不同建模方式的鋼-混凝土有限元模型,結(jié)果表明殼-實體模型能夠很好地反映出組合結(jié)構(gòu)的真實靜動力性能。然后,基于靜動力數(shù)據(jù)對基準(zhǔn)模型的物理參數(shù)進(jìn)行靈敏度分析,選取靈敏度高的4個參數(shù)進(jìn)行多參數(shù)模型校驗。最后,基于獲得的靜動力試驗數(shù)據(jù)和Strand7模型分析結(jié)果,通過引入Teughels損傷函數(shù)識別出了試驗板的剛度退化分布。
[Abstract]:Steel-concrete composite structure is a common form of bridge structure. It is of great significance to study the structure identification of steel-concrete composite structure. Based on the previous research results, the static and dynamic load tests and modal flexibility identification of a laboratory steel-concrete composite deck slab and a steel-concrete composite structure bridge are studied in this paper. The main contents of this paper are as follows: (1) two modal flexibility calculation methods are summarized theoretically, and two modal identification methods are proposed to solve the modal flexibility in essence. Using the characteristics of the two methods to transform each other, the quality of the structure can be obtained. At the same time, the theory of obtaining the overall modal flexibility of the structure by piecewise test is put forward. The process is to splice the substructure mass normalized mode to obtain the expansion of the integral mode. Then the finite element model of a concrete slab and a laboratory steel-concrete composite slab are tested by pulse hammer test using the integral flexibility matrix of the jointed mode calculation structure. The results show that SISO, SIMO and MIMOM) can obtain the modal flexibility coefficient more accurately than the other methods, such as single-point input and single-point output (SISO), single-point input multi-point output (SIMO) and multi-point input multi-point output (MIMOO). The modal flexibility matrix with small difference from the static method can be obtained by the substructure mode splicing method. The feasibility of using this method in practical application is verified by testing the pulse hammer method of a practical bridge. At the same time, the model quality normalization under random vibration test is carried out. The finite element numerical test and the random vibration test in laboratory show that the modal flexibility of the structure can be obtained by random vibration test based on the assumption of lumped mass matrix. The result is more flexible than the actual structure. Firstly, three kinds of damage conditions, such as stiffness change of support, joint damage and transverse bracing failure, are designed to simulate the possible damage conditions of actual bridge structures. By comparing the modal flexibility and displacement information before and after structural damage, the damage identification of composite plate is successfully realized. The results show that modal flexibility is an excellent damage index and its sensitivity to damage is much greater than that of frequency and mode shape. Secondly, the static damage of the test plate is caused by static loading. The static damage location and damage degree are identified successfully by modal compliance method. The finite element model of steel-concrete composite slab structure is modified based on the API interactive access technique of Strand7 finite element software and Mat lab application program. Firstly, three kinds of steel-concrete finite element models with different modeling methods are compared. The results show that the shell-solid model can well reflect the real static and dynamic performance of composite structures. Then, based on the static and dynamic data, the physical parameters of the benchmark model are analyzed, and the four parameters with high sensitivity are selected to verify the multi-parameter model. Finally, based on the obtained static and dynamic test data and the results of Strand7 model analysis, the stiffness degradation distribution of the test plate is identified by introducing the Teughels damage function.
【學(xué)位授予單位】：湖南大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：U446

【參考文獻(xiàn)】

相關(guān)期刊論文 前8條

1 吉伯海;傅中秋;;近年國內(nèi)橋梁倒塌事故原因分析[J];土木工程學(xué)報;2010年S1期

2 李永梅;周錫元;高向宇;;基于柔度差曲率矩陣的結(jié)構(gòu)損傷識別方法[J];工程力學(xué);2009年02期

3 徐洪濤;郭國忠;蒲煥玲;苑敏;;我國近年來橋梁事故發(fā)生的原因與教訓(xùn)[J];中國安全科學(xué)學(xué)報;2007年11期

4 張宇峰;徐宏;倪一清;;大跨橋梁結(jié)構(gòu)健康監(jiān)測及安全評價系統(tǒng)研究與應(yīng)用進(jìn)展[J];公路;2005年12期

5 葉梅新,黃瓊;高速鐵路鋼—混凝土組合梁的損傷識別[J];中南大學(xué)學(xué)報(自然科學(xué)版);2005年04期

6 孫國,顧元憲;連續(xù)梁結(jié)構(gòu)損傷識別的改進(jìn)柔度陣方法[J];工程力學(xué);2003年04期

7 葉梅新,黃瓊;鋼結(jié)構(gòu)事故研究[J];長沙鐵道學(xué)院學(xué)報;2002年04期

8 郭向榮,曾慶元;高速鐵路結(jié)合梁橋與列車系統(tǒng)振動分析模型[J];華中理工大學(xué)學(xué)報;2000年03期

，

本文編號：1776386