本文選題：橋梁結(jié)構(gòu) + 安全性能��； 參考：《中國民航大學(xué)》2015年碩士論文

【摘要】：目前已有的橋梁結(jié)構(gòu)檢測(cè)方法主要有靜力荷載試驗(yàn)法和動(dòng)力試驗(yàn)法。其中靜載試驗(yàn)法需長(zhǎng)時(shí)間中斷交通、耗時(shí)耗力;已有的動(dòng)力試驗(yàn)法多以獲得橋梁結(jié)構(gòu)的模態(tài)信息作為評(píng)價(jià)橋梁結(jié)構(gòu)性能的依據(jù),其理論方法尚不夠成熟,且實(shí)測(cè)數(shù)據(jù)對(duì)結(jié)構(gòu)損傷靈敏度較弱。擬靜力荷載試驗(yàn)是介于靜力荷載試驗(yàn)和動(dòng)力荷載試驗(yàn)之間的一種試驗(yàn)方法。通過對(duì)實(shí)測(cè)應(yīng)變或撓度影響線分析對(duì)橋梁結(jié)構(gòu)承載能力進(jìn)行評(píng)定。擬靜力荷載試驗(yàn)由于其對(duì)試驗(yàn)方法及數(shù)據(jù)采集設(shè)備的精度要求較高,在我國一直未得到大范圍的應(yīng)用。本課題在河北省交通科學(xué)基金資助下,提出基于動(dòng)態(tài)試驗(yàn)的橋梁快速診斷技術(shù)。動(dòng)態(tài)試驗(yàn)包括動(dòng)力模態(tài)試驗(yàn)和動(dòng)力荷載荷載試驗(yàn)。動(dòng)力模態(tài)試驗(yàn)通過采集橋梁結(jié)構(gòu)在正常交通量和大地振動(dòng)激勵(lì)下的加速度信號(hào),對(duì)實(shí)測(cè)數(shù)據(jù)作傅里葉變換,得到橋梁結(jié)構(gòu)的頻率、振型、阻尼比、剛度等。動(dòng)力荷載試驗(yàn)通過在橋面施加指定路徑的標(biāo)準(zhǔn)加載車車輛荷載,采集橋梁結(jié)構(gòu)各測(cè)點(diǎn)的應(yīng)變或撓度影響線。以兩種試驗(yàn)獲得的橋梁結(jié)構(gòu)的力學(xué)響應(yīng)為依據(jù),修正橋梁結(jié)構(gòu)的有限元模型。模型優(yōu)化過程中采用合理的設(shè)計(jì)變量、狀態(tài)變量和有效的目標(biāo)函數(shù)。將相同荷載工況下橋梁結(jié)構(gòu)有限元模型的計(jì)算值與實(shí)測(cè)值進(jìn)行比對(duì),借助大型有限元軟件ANSYS中的優(yōu)化模塊,不斷調(diào)整設(shè)計(jì)變量的取值,直至有限元計(jì)算值與實(shí)測(cè)值誤差無限小,即認(rèn)為橋梁結(jié)構(gòu)有限元模型修正完成,此時(shí)有限元模型等效于實(shí)際橋梁結(jié)構(gòu)力學(xué)模型。在修正好的室內(nèi)橋梁結(jié)構(gòu)有限元模型上施加滿足加載效率的靜力荷載,利用靜力荷載試驗(yàn)法評(píng)價(jià)橋梁結(jié)構(gòu)的理論,對(duì)橋梁結(jié)構(gòu)性能作出評(píng)價(jià),從而達(dá)到快速有效評(píng)價(jià)橋梁健康狀況的目的。針對(duì)本課題提出的基于動(dòng)態(tài)試驗(yàn)的橋梁快速診斷技術(shù),本論文做了如下幾方面的研究:1.針對(duì)橋梁結(jié)構(gòu)可能出現(xiàn)的各種損傷,通過室內(nèi)有限元仿真模擬,研究了橋梁結(jié)構(gòu)出現(xiàn)橫向連接損傷、梁底裂縫等損傷時(shí),動(dòng)態(tài)試驗(yàn)實(shí)測(cè)結(jié)果的變化。為實(shí)際橋梁檢測(cè)工程提供了理論支持,為試驗(yàn)方案的合理選擇提供了依據(jù)。2.研究了配筋率、彈性模量、截面慣性矩對(duì)應(yīng)變或撓度影響線的影響規(guī)律及影響程度,為有限元模型修正過程中設(shè)計(jì)變量的合理選取提供理論依據(jù)。3.建立了基于動(dòng)力模態(tài)參數(shù)和應(yīng)變影響線的橋梁結(jié)構(gòu)初始有限元模型校準(zhǔn)技術(shù)中的目標(biāo)函數(shù),通過合理選擇目標(biāo)函數(shù)的表達(dá)式,保證結(jié)構(gòu)模型優(yōu)化的收斂性和有效性,為橋梁結(jié)構(gòu)有限元模型優(yōu)化提供了依據(jù)。4.將本課題所提出的橋梁快速檢測(cè)方法應(yīng)用于機(jī)場(chǎng)滑行道橋和公路橋?qū)嶋H檢測(cè)工程。借助橋梁實(shí)際檢測(cè)工程詳細(xì)介紹了動(dòng)力模態(tài)試驗(yàn)和動(dòng)力荷載試驗(yàn)的數(shù)據(jù)采集、分析過程,以及模型優(yōu)化、仿真靜力加載、橋梁結(jié)構(gòu)評(píng)價(jià)的全過程,驗(yàn)證了本論文所提出方法的可行性。
[Abstract]:At present, the existing methods of bridge structure testing mainly include static load test method and dynamic test method. Among them, the static load test method needs to interrupt traffic for a long time, which is time-consuming and labor-consuming. Most of the existing dynamic test methods take the modal information of bridge structure as the basis for evaluating the performance of bridge structure, and its theoretical method is not mature enough. The sensitivity of measured data to structural damage is weak. Pseudostatic load test is a test method between static load test and dynamic load test. The bearing capacity of bridge structure is evaluated by analyzing the influence line of measured strain or deflection. Quasi-static load test has not been widely used in China because of its high precision requirements for test methods and data acquisition equipment. In this paper, a bridge rapid diagnosis technique based on dynamic test is proposed, supported by Hebei Provincial Traffic Science Foundation. Dynamic test includes dynamic modal test and dynamic load test. By collecting the acceleration signals of the bridge structure under the excitation of normal traffic volume and earth vibration, the dynamic modal test carries out Fourier transform to the measured data, and obtains the frequency, mode shape, damping ratio, stiffness and so on of the bridge structure. By applying the standard loading vehicle load on the bridge deck, the strain or deflection influence lines of each measuring point of the bridge structure are collected. Based on the mechanical response of bridge structure obtained by two kinds of tests, the finite element model of bridge structure is modified. Reasonable design variables, state variables and effective objective functions are used in the process of model optimization. Comparing the calculated value with the measured value of the finite element model of the bridge structure under the same load condition, with the help of the optimization module in the large-scale finite element software ANSYS, the value of the design variable is adjusted continuously until the error between the finite element calculation value and the measured value is infinitesimally small. It is considered that the finite element model of bridge structure is modified, and the finite element model is equivalent to the actual bridge structural mechanics model. Applying static load to the modified finite element model of indoor bridge structure to satisfy the loading efficiency, the theory of static load test method is used to evaluate the performance of bridge structure. In order to quickly and effectively evaluate the health status of the bridge. Aiming at the bridge rapid diagnosis technology based on dynamic test, this paper has done the following research: 1: 1. In view of the possible damage of bridge structure, the change of the measured results of dynamic test is studied when the bridge structure is damaged by transverse connection damage and beam bottom crack by means of indoor finite element simulation. It provides theoretical support for the actual bridge detection project and provides the basis for the reasonable selection of the test scheme. The influence of reinforcement ratio, elastic modulus and moment of inertia of section on the influence line of strain or deflection is studied, which provides a theoretical basis for the reasonable selection of design variables in the process of modification of finite element model. The objective function of the initial finite element model calibration technique for bridge structures based on dynamic modal parameters and strain influence lines is established. The convergence and effectiveness of structural model optimization are ensured by selecting the expression of the objective function reasonably. It provides the basis for the optimization of finite element model of bridge structure. The proposed method is applied to the practical detection of taxiway bridge and highway bridge. The data acquisition and analysis process of dynamic modal test and dynamic load test, as well as the whole process of model optimization, simulation static loading and bridge structure evaluation are introduced in detail with the help of bridge actual testing project. The feasibility of the proposed method is verified.
【學(xué)位授予單位】：中國民航大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：U446

【參考文獻(xiàn)】

相關(guān)期刊論文 前4條

1 丁幼亮;李愛群;繆長(zhǎng)青;李兆霞;韓曉林;;大跨橋梁結(jié)構(gòu)損傷診斷與安全評(píng)估的多尺度有限元模擬研究[J];地震工程與工程振動(dòng);2006年02期

2 黃立葵;盛燦花;;車輛動(dòng)荷系數(shù)與路面平整度的關(guān)系[J];公路交通科技;2006年03期

3 劉東,廖日東,左正興;分析/試驗(yàn)?zāi)Ｐ拖嚓P(guān)及修正技術(shù)若干問題[J];強(qiáng)度與環(huán)境;2003年01期

4 李鴻儀;;理想化最速下降法及其逼近實(shí)例[J];上海第二工業(yè)大學(xué)學(xué)報(bào);2011年01期

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本文編號(hào)：2095667