大跨徑鋼管混凝土拱橋桁架拱肋耐久性評(píng)估研究
發(fā)布時(shí)間：2018-12-14 06:18
【摘要】：由于環(huán)境和時(shí)間因素的影響，鋼管混凝土拱橋出現(xiàn)鋼管銹蝕、混凝土脫空等耐久性病害從而導(dǎo)致鋼管混凝土結(jié)構(gòu)的耐久性發(fā)生退化，結(jié)構(gòu)承載力隨之下降，最終導(dǎo)致橋梁的使用受到限制甚至發(fā)生橋梁坍塌等，而鋼管混凝土拱橋桁架拱肋作為主要的承重結(jié)構(gòu)和傳力結(jié)構(gòu)，弦桿和腹桿等桿件眾多結(jié)構(gòu)復(fù)雜，其狀態(tài)直接決定著拱橋的使用壽命，因此對(duì)其耐久性病害損傷的狀況評(píng)定是十分必要的。 本文運(yùn)用傳統(tǒng)的模糊層次法對(duì)桁架拱肋進(jìn)行了詳細(xì)的遞階分層，劃分鋼管、混凝土、其它損傷項(xiàng)目層，通過(guò)模糊層次評(píng)估法得到鋼管、混凝土等不同項(xiàng)目層和拱肋目標(biāo)對(duì)象的評(píng)估結(jié)果，利用變權(quán)原理和模糊貼近度處理等評(píng)估技巧使得評(píng)估更加準(zhǔn)確。避免了現(xiàn)有的拱肋的耐久性評(píng)估病害劃分和評(píng)估比較粗糙的缺陷。 本文針對(duì)桁架拱肋的復(fù)雜結(jié)構(gòu)特點(diǎn)運(yùn)用可靠度理論結(jié)合模糊評(píng)估方法，建立了桁架拱肋的基于可靠度的模糊層次評(píng)估模型。該方法的主要內(nèi)容與結(jié)論如下： ①將桁架拱肋這一復(fù)雜結(jié)構(gòu)將實(shí)橋和有限元模型結(jié)合進(jìn)行單元?jiǎng)澐�，將桁架拱肋拆解成各單元�?gòu)件，這樣可以使評(píng)估細(xì)化到拱肋的細(xì)小部位，避免了過(guò)去對(duì)于桁架拱肋只能進(jìn)行整體的病害評(píng)估的缺點(diǎn)。 ②結(jié)合設(shè)計(jì)荷載作用下的MIDAS/Civil的分析內(nèi)力結(jié)果，引入能量法中應(yīng)變能的計(jì)算方法，計(jì)算桁架拱肋各部位（單元構(gòu)件）的權(quán)重，得到拱肋的內(nèi)力和權(quán)重的數(shù)值分布規(guī)律。該權(quán)重計(jì)算方法結(jié)合了荷載作用和構(gòu)件自身材料特性，避免了傳統(tǒng)權(quán)重計(jì)算方法的主觀性、片面性與粗糙賦值的缺陷。 ③根據(jù)構(gòu)件的損傷情況和單元（實(shí)橋拱肋的各部位）內(nèi)力求解單元構(gòu)件的可靠度，由單元權(quán)重和構(gòu)件可靠度運(yùn)用簡(jiǎn)捷的體系可靠度計(jì)算公式計(jì)算桁架拱肋的體系可靠度，建立鋼管混凝土拱橋的構(gòu)件和體系可靠性評(píng)估分級(jí)標(biāo)準(zhǔn)，根據(jù)分級(jí)標(biāo)準(zhǔn)對(duì)桁架拱肋各單元構(gòu)件（拱肋部位）和整個(gè)拱肋分別進(jìn)行耐久性病害下的可靠性評(píng)估。并在構(gòu)件損傷的可靠性評(píng)估結(jié)果的基礎(chǔ)上結(jié)合所有桁架拱肋的耐久性病害進(jìn)行桁架拱肋整體的模糊層次評(píng)估。 ④評(píng)估實(shí)例表明基于結(jié)構(gòu)可靠度的耐久性評(píng)估方法與傳統(tǒng)模糊層次評(píng)估方法結(jié)果相近，符合橋梁實(shí)際耐久性狀態(tài)。但前者可以得到桁架拱肋這一復(fù)雜結(jié)構(gòu)的內(nèi)力和權(quán)重分布規(guī)律，單元構(gòu)件可靠度和拱肋整體可靠度評(píng)估結(jié)果，，以及所有病害下的拱肋模糊評(píng)估結(jié)果，評(píng)估結(jié)論全面且評(píng)估過(guò)程中考慮荷載和病害影響下的拱肋自身抗力衰減，對(duì)后期拱肋的養(yǎng)護(hù)、維修指導(dǎo)意義更大。
[Abstract]:Due to the influence of environment and time, the durability of concrete-filled steel tube (CFST) arch bridge is damaged by corrosion of steel tube and concrete void, which leads to the degradation of the durability of CFST structure and the decrease of the bearing capacity of CFST structure. Finally, the use of the bridge is restricted or even the bridge collapses. As the main load-bearing structure and force transfer structure, the truss arch rib of concrete-filled steel tubular arch bridge is complex, such as chord and web bar. The service life of arch bridge is directly determined by its state, so it is necessary to evaluate the condition of durability damage. In this paper, the traditional fuzzy hierarchy method is used to stratify the truss arch rib in detail, dividing the steel tube, concrete and other damage item layers, and obtaining the steel pipe by the fuzzy hierarchy evaluation method. The evaluation results of different project layers and arch ribbed objects, such as concrete, are more accurate by using variable weight principle and fuzzy closeness processing techniques. The existing arch-ribbed durability assessment of disease classification and evaluation of rough defects. In this paper, according to the complex structural characteristics of truss arch rib, the reliability theory and fuzzy evaluation method are used to establish the reliability based fuzzy hierarchy evaluation model of truss arch rib. The main contents and conclusions of this method are as follows: (1) the truss arch rib is divided into elements by combining the real bridge with the finite element model, and the arch rib of the truss is disassembled into each element member. In this way, the evaluation can be refined to the small part of the arch rib, avoiding the shortcoming that the arch rib of truss can only be evaluated as a whole in the past. (2) combined with the analysis of internal force of MIDAS/Civil under design load, the calculation method of strain energy in energy method is introduced to calculate the weight of each part of truss arch rib (element member), and the numerical distribution law of internal force and weight of arch rib is obtained. The weight calculation method combines the load action and the material characteristics of the member itself, and avoids the disadvantages of subjectivity, one-sidedness and rough assignment of the traditional weight calculation method. (3) according to the damage condition of the member and the internal force of the element (every part of the arch rib of the real bridge), the reliability of the element member is solved, and the system reliability of the truss arch rib is calculated by using the simple formula of the system reliability by using the weight of the element and the reliability of the member. The reliability evaluation criteria of concrete filled steel tube (CFST) arch bridge were established. According to the classification criteria, the reliability of each element of truss arch rib (arch rib) and the whole arch rib were evaluated under the durability disease respectively. Based on the results of reliability assessment of member damage, the fuzzy hierarchy assessment of the whole truss arch rib is carried out based on the durability disease of all truss arch ribs. (4) the evaluation example shows that the durability evaluation method based on structural reliability is similar to the traditional fuzzy hierarchy process and accords with the actual durability state of the bridge. However, the former can obtain the distribution law of internal force and weight of the complex structure of truss arch rib, the evaluation results of the reliability of element member and the whole reliability of arch rib, as well as the fuzzy evaluation result of arch rib under all diseases. The comprehensive evaluation conclusion and the resistance attenuation of arch rib under the influence of load and disease in the evaluation process are of great significance to the maintenance and maintenance of the arch rib in the later stage.
【學(xué)位授予單位】：重慶交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類(lèi)號(hào)】：U448.22;U441
本文編號(hào)：2378078
[Abstract]:Due to the influence of environment and time, the durability of concrete-filled steel tube (CFST) arch bridge is damaged by corrosion of steel tube and concrete void, which leads to the degradation of the durability of CFST structure and the decrease of the bearing capacity of CFST structure. Finally, the use of the bridge is restricted or even the bridge collapses. As the main load-bearing structure and force transfer structure, the truss arch rib of concrete-filled steel tubular arch bridge is complex, such as chord and web bar. The service life of arch bridge is directly determined by its state, so it is necessary to evaluate the condition of durability damage. In this paper, the traditional fuzzy hierarchy method is used to stratify the truss arch rib in detail, dividing the steel tube, concrete and other damage item layers, and obtaining the steel pipe by the fuzzy hierarchy evaluation method. The evaluation results of different project layers and arch ribbed objects, such as concrete, are more accurate by using variable weight principle and fuzzy closeness processing techniques. The existing arch-ribbed durability assessment of disease classification and evaluation of rough defects. In this paper, according to the complex structural characteristics of truss arch rib, the reliability theory and fuzzy evaluation method are used to establish the reliability based fuzzy hierarchy evaluation model of truss arch rib. The main contents and conclusions of this method are as follows: (1) the truss arch rib is divided into elements by combining the real bridge with the finite element model, and the arch rib of the truss is disassembled into each element member. In this way, the evaluation can be refined to the small part of the arch rib, avoiding the shortcoming that the arch rib of truss can only be evaluated as a whole in the past. (2) combined with the analysis of internal force of MIDAS/Civil under design load, the calculation method of strain energy in energy method is introduced to calculate the weight of each part of truss arch rib (element member), and the numerical distribution law of internal force and weight of arch rib is obtained. The weight calculation method combines the load action and the material characteristics of the member itself, and avoids the disadvantages of subjectivity, one-sidedness and rough assignment of the traditional weight calculation method. (3) according to the damage condition of the member and the internal force of the element (every part of the arch rib of the real bridge), the reliability of the element member is solved, and the system reliability of the truss arch rib is calculated by using the simple formula of the system reliability by using the weight of the element and the reliability of the member. The reliability evaluation criteria of concrete filled steel tube (CFST) arch bridge were established. According to the classification criteria, the reliability of each element of truss arch rib (arch rib) and the whole arch rib were evaluated under the durability disease respectively. Based on the results of reliability assessment of member damage, the fuzzy hierarchy assessment of the whole truss arch rib is carried out based on the durability disease of all truss arch ribs. (4) the evaluation example shows that the durability evaluation method based on structural reliability is similar to the traditional fuzzy hierarchy process and accords with the actual durability state of the bridge. However, the former can obtain the distribution law of internal force and weight of the complex structure of truss arch rib, the evaluation results of the reliability of element member and the whole reliability of arch rib, as well as the fuzzy evaluation result of arch rib under all diseases. The comprehensive evaluation conclusion and the resistance attenuation of arch rib under the influence of load and disease in the evaluation process are of great significance to the maintenance and maintenance of the arch rib in the later stage.
【學(xué)位授予單位】：重慶交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類(lèi)號(hào)】：U448.22;U441
【參考文獻(xiàn)】
相關(guān)期刊論文 前9條
1 張紹良,張國(guó)良;灰色關(guān)聯(lián)度計(jì)算方法比較及其存在問(wèn)題分析[J];系統(tǒng)工程;1996年03期
2 魏建東;宜賓小南門(mén)大橋的搶修加固與恢復(fù)工程[J];公路;2003年04期
3 周海龍,周水興,劉文方;鋼管混凝土拱橋的應(yīng)用與發(fā)展[J];公路交通技術(shù);2005年03期
4 白寶鴻;法國(guó)昂特那斯鋼管拱橋[J];國(guó)外橋梁;1998年03期
5 陳寶春;鋼管混凝土拱橋發(fā)展綜述[J];橋梁建設(shè);1997年02期
6 貢金鑫,趙國(guó)藩;結(jié)構(gòu)可靠度分析中的最小方差抽樣[J];上海力學(xué);1996年03期
7 張雷明;劉西拉;;框架結(jié)構(gòu)能量流網(wǎng)絡(luò)及其初步應(yīng)用[J];土木工程學(xué)報(bào);2007年03期
8 劉文奇;均衡函數(shù)及其在變權(quán)綜合中的應(yīng)用[J];系統(tǒng)工程理論與實(shí)踐;1997年04期
9 鄭強(qiáng),孫國(guó)安;佛陳大橋缺陷原因分析及加固[J];中國(guó)鐵道科學(xué);2000年04期
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