本文選題：城市橋梁 + 爆炸荷載�。� 參考：《天津大學(xué)》2014年碩士論文

【摘要】：城市橋梁作為陸地交通的咽喉，在國(guó)民經(jīng)濟(jì)和軍事交通中均具有至關(guān)重要的地位和作用。它的建造不但方便了人們的出行，而且在高度快速、機(jī)動(dòng)的現(xiàn)代生活中具有非常重要的地位。然而，隨著日益嚴(yán)重的反恐形勢(shì)，恐怖襲擊或各種偶然爆炸等事故也越來越頻繁，因此，炸彈爆炸所引發(fā)的城市橋梁爆炸失效問題越來越引起人們的重視。炸藥在關(guān)鍵部位爆炸可能會(huì)給橋梁結(jié)構(gòu)造成巨大的破壞，導(dǎo)致城市交通擁堵與中斷，甚至造成大規(guī)模的人員傷亡。研究城市橋梁爆炸失效機(jī)理，及時(shí)地運(yùn)用合理的方法確認(rèn)出橋梁發(fā)生爆炸后的損傷狀況，準(zhǔn)確、科學(xué)地對(duì)橋梁結(jié)構(gòu)的安全性進(jìn)行評(píng)估具有重要意義。雖然對(duì)城市橋梁抗爆方面的研究已受到國(guó)內(nèi)外研究人員和工程設(shè)計(jì)人員的廣泛關(guān)注，但城市橋梁在爆炸荷載作用下的安全評(píng)估尚未得到足夠程度的重視，取得的成果極其有限，很多成果無法直接應(yīng)用于工程實(shí)踐。因此，有必要提出一種實(shí)用且便捷的城市橋梁抗爆安全評(píng)估方法�；谝延谐晒疚膶�(duì)城市橋梁爆炸失效機(jī)理及其安全評(píng)估方法開展了系統(tǒng)的研究，具體內(nèi)容如下： 1、系統(tǒng)研究了爆炸基本現(xiàn)象、爆炸沖擊波的基本理論，總結(jié)了爆炸沖擊波各參數(shù)的經(jīng)驗(yàn)計(jì)算公式。 2、系統(tǒng)闡述了爆炸荷載作用下城市橋梁失效機(jī)理與損傷機(jī)制的數(shù)值模擬方法。 3、根據(jù)爆炸荷載引起橋梁整體結(jié)構(gòu)或者局部構(gòu)件的損傷特點(diǎn)，并結(jié)合城市橋梁的現(xiàn)狀，提出了一種用于評(píng)估爆炸荷載作用下城市橋梁安全性的數(shù)值模擬方法。首先提出了一種基于材料屈服強(qiáng)度和爆炸荷載作用后各控制截面上最大累積應(yīng)力的安全指數(shù)的計(jì)算公式，然后分析城市橋梁在爆炸荷載作用下的動(dòng)態(tài)響應(yīng)，得到爆炸事故發(fā)生后橋梁控制截面上最大累積應(yīng)力，從而計(jì)算出橋梁的安全指數(shù)，最終依據(jù)橋梁的安全指數(shù)對(duì)橋梁整體進(jìn)行安全評(píng)估。 4、以國(guó)內(nèi)某城市中心區(qū)主干道一座跨河的大型鋼桁架組合拱橋?yàn)楸尘埃⒂邢拊?jì)算模型，運(yùn)用大型非線性有限元軟件ANSYS/LS-DYNA對(duì)該橋的動(dòng)態(tài)響應(yīng)以及安全性進(jìn)行系統(tǒng)分析與評(píng)估，得出在不同計(jì)算工況下橋梁的安全性狀況，，另外，通過不同工況的計(jì)算結(jié)果的對(duì)比，獲得炸藥量、炸藥所在的車道位置以及縱橋向位置對(duì)橋梁安全性的影響規(guī)律。
[Abstract]:As the throat of land traffic, urban bridges play an important role in national economy and military traffic. Its construction not only facilitates people to travel, but also plays a very important role in the high speed and mobility of modern life. However, with the increasingly serious anti-terrorist situation, terrorist attacks or various accidental explosions are more and more frequent. Therefore, the explosion failure of urban bridges caused by bomb explosion has attracted more and more attention. Explosive explosion in key areas may cause great damage to the bridge structure, lead to traffic congestion and interruption, and even cause massive casualties. It is of great significance to study the failure mechanism of urban bridge explosion and confirm the damage condition of bridge after explosion by using reasonable method in time. It is of great significance to evaluate the safety of bridge structure scientifically and accurately. Although the research on anti-explosion of urban bridges has been widely concerned by researchers and engineers at home and abroad, the safety assessment of urban bridges under explosion load has not been paid enough attention to, and the results obtained are extremely limited. Many achievements can not be directly applied to engineering practice. Therefore, it is necessary to put forward a practical and convenient method for evaluating the anti-explosion safety of urban bridges. Based on the existing achievements, this paper has carried out a systematic study on the explosion failure mechanism and safety assessment methods of urban bridges. The specific contents are as follows: 1. The basic phenomena of explosion and the basic theory of explosion shock wave are systematically studied. The empirical formulas for calculating the parameters of explosion shock wave are summarized. 2. The numerical simulation method of failure mechanism and damage mechanism of urban bridge under explosion load is systematically expounded. The damage characteristics of the whole structure or local members of a bridge, Combined with the present situation of urban bridges, a numerical simulation method for evaluating the safety of urban bridges under explosive load is proposed. In this paper, a formula for calculating the safety index based on the maximum cumulative stress of each control section after material yield strength and explosive load is proposed, and then the dynamic response of urban bridges under explosion load is analyzed. The maximum accumulated stress on the control section of the bridge after the explosion accident is obtained, and the safety index of the bridge is calculated. Finally, according to the safety index of the bridge, the overall safety of the bridge is evaluated. 4. Taking a large steel truss composite arch bridge across the river in the main road of a central city in China as the background, the finite element calculation model is established. The dynamic response and safety of the bridge are systematically analyzed and evaluated by using the large-scale nonlinear finite element software ANSYS- LS-DYNA, and the safety conditions of the bridge under different calculation conditions are obtained. The influence of explosive quantity, lane position and longitudinal bridge position on bridge safety is obtained.
【學(xué)位授予單位】：天津大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：U441

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 熊祖釗,白春華,劉長(zhǎng)林;燃料空氣炸藥爆炸壓力場(chǎng)測(cè)試系統(tǒng)誤差分析[J];爆破;2001年04期

2 孔新立;金豐年;蔣美蓉;;恐怖爆炸襲擊方式及規(guī)模分析[J];爆破;2007年03期

3 劉山洪,魏建東,錢永久;橋梁結(jié)構(gòu)爆炸分析特點(diǎn)綜述[J];重慶交通學(xué)院學(xué)報(bào);2005年03期

4 伍俊;劉晶波;杜義欣;;汽車炸彈爆炸下裝配式防爆墻彈塑性動(dòng)力計(jì)算與數(shù)值分析[J];防災(zāi)減災(zāi)工程學(xué)報(bào);2007年04期

5 辛宇天;任勁松;凡小杰;;橋梁面臨的威脅及防護(hù)[J];光電技術(shù)應(yīng)用;2005年06期

6 周志斌,葛強(qiáng)林;未來交通重點(diǎn)目標(biāo)防護(hù)偽裝展望[J];國(guó)防交通工程與技術(shù);2003年01期

7 張彥玲,李運(yùn)生,王海龍;既有橋梁承載力評(píng)估方法研究[J];國(guó)防交通工程與技術(shù);2003年01期

8 葛強(qiáng)勝;大型橋梁抗激光制導(dǎo)炸彈襲擊對(duì)策探討[J];國(guó)防交通工程與技術(shù);2003年04期

9 劉寶新;薛勛國(guó);;大型橋梁的綜合集成防護(hù)應(yīng)用[J];國(guó)防交通工程與技術(shù);2005年04期

10 王凱;李海超;王曉安;;精確制導(dǎo)武器威脅下的深水大跨度橋梁戰(zhàn)時(shí)保障對(duì)策研究[J];國(guó)防交通工程與技術(shù);2010年01期

相關(guān)博士學(xué)位論文 前1條

1 李天華;爆炸荷載下鋼筋混凝土板的動(dòng)態(tài)響應(yīng)及損傷評(píng)估[D];長(zhǎng)安大學(xué);2012年

本文編號(hào)：2109047