本文關(guān)鍵詞：U肋與頂板連接焊縫殘余應(yīng)力的三維數(shù)值模擬　出處：《西南交通大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： U肋與頂板焊縫 殘余應(yīng)力 溫度場 應(yīng)力場 數(shù)值模擬

【摘要】：正交異性鋼橋面板因經(jīng)濟(jì)耐久,輕質(zhì)高強(qiáng)等優(yōu)點,被廣泛運用于世界大、中跨度橋梁。但其結(jié)構(gòu)復(fù)雜,板件眾多,大都通過焊接方式連接,焊縫處必然存在殘余應(yīng)力。焊接殘余應(yīng)力的存在會降低鋼橋面板的使用性能,如抗腐蝕、抗疲勞和穩(wěn)定性能等。當(dāng)前完全控制和消除焊接殘余應(yīng)力還不太現(xiàn)實,鋼橋面板上還會存在很大的殘余應(yīng)力。為保證鋼橋面板的使用安全,需要準(zhǔn)確認(rèn)識殘余應(yīng)力的大小及其分布規(guī)律。殘余應(yīng)力的試驗測量耗時耗力,論文采用數(shù)值模擬技術(shù)進(jìn)行定量分析,主要工作包括：(1)簡單介紹了焊接殘余應(yīng)力的基礎(chǔ)知識,回顧了焊接數(shù)值模擬技術(shù)的國內(nèi)外發(fā)展現(xiàn)狀,并總結(jié)了焊接模擬的相關(guān)理論和方法,包括焊接溫度場和應(yīng)力場的理論；(2)以港珠澳大橋為背景,采用ANSYS有限元軟件建立U肋與頂板連接焊縫的三維模型,選定合理的材料參數(shù)和熱源模型,使用生死單元技術(shù)模擬焊料的熔化和填充,分別進(jìn)行溫度場和應(yīng)力場的模擬計算；(3)對模擬計算結(jié)果進(jìn)行分析,得到溫度場和應(yīng)力場的分布規(guī)律：熱源移動位置,焊縫金屬溫度急劇升高至熔融,隨著熱源的離開,溫度又迅速下降最終至室溫；頂板近U肋表面焊縫區(qū)的最大殘余拉應(yīng)力約為屈服強(qiáng)度的1.2倍,遠(yuǎn)焊縫區(qū)的最大殘余壓應(yīng)力約為屈服強(qiáng)度的0.1倍；U肋近焊縫區(qū)的最大殘余拉應(yīng)力達(dá)到屈服強(qiáng)度,遠(yuǎn)焊縫區(qū)的最大殘余壓應(yīng)力約為屈服強(qiáng)度的0.1倍；(4)分析材料參數(shù)、焊接工藝參數(shù)和幾何模型參數(shù)對焊接殘余應(yīng)力的影響,得到更為準(zhǔn)確的模擬計算結(jié)果,為合理的焊接工藝提供數(shù)據(jù)支持；模擬計算結(jié)果說明：U肋與頂板連接焊縫殘余應(yīng)力是可以用ANSYS軟件進(jìn)行數(shù)值模擬的；頂板和U肋殘余應(yīng)力的計算結(jié)果和分布趨勢與前人的研究相接近;參數(shù)變化對焊接殘余應(yīng)力的影響很大。
[Abstract]:Orthotropic steel bridge panel is widely used in the world because of its advantages such as economic durability, light weight and high strength, but its structure is complex and its panels are numerous, most of them are connected by welding. Welding residual stress will reduce the performance of steel bridge panel, such as corrosion resistance, fatigue resistance and stability, etc. At present, it is not practical to completely control and eliminate welding residual stress. In order to ensure the safety of steel bridge panel, it is necessary to understand the magnitude and distribution of residual stress accurately, and the test measurement of residual stress is time-consuming and labor-consuming. In this paper, numerical simulation technology is used for quantitative analysis. The main work includes: 1) the basic knowledge of welding residual stress is briefly introduced, and the development status of welding numerical simulation technology at home and abroad is reviewed. The related theories and methods of welding simulation are summarized, including the theory of welding temperature field and stress field. (2) taking HongKong-Zhuhai-Macao Bridge as the background, the ANSYS finite element software is used to establish the three-dimensional model of U-rib and roof joint weld, and the reasonable material parameters and heat source model are selected. The melting and filling of solder were simulated by birth and death element technique, and the temperature field and stress field were simulated and calculated respectively. The distribution of temperature field and stress field is obtained by analyzing the simulation results: the temperature of weld metal rises sharply to melting when the heat source moves, and with the departure of heat source. The temperature drops rapidly to room temperature; The maximum residual tensile stress near the surface of U rib is about 1.2 times of yield strength, and the maximum residual compressive stress of far weld is 0.1 times of yield strength. The maximum residual tensile stress of U-rib near weld reaches yield strength, and the maximum residual compressive stress of far-weld is about 0.1 times of yield strength. 4) analyzing the influence of material parameters, welding process parameters and geometric model parameters on welding residual stress, and obtaining more accurate simulation results, which provide data support for reasonable welding process. The simulation results show that the residual stress of weld joint between U rib and roof can be numerically simulated by ANSYS software. The calculated results and distribution trend of residual stress in roof and U-rib are close to those of previous studies. The variation of parameters has great influence on welding residual stress.
【學(xué)位授予單位】：西南交通大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：U445.583

【參考文獻(xiàn)】

相關(guān)期刊論文 前5條

1 董世柱,李麗,趙海宏,霍樹斌,王佳杰;焊接結(jié)構(gòu)中疲勞裂紋形成位置與過程[J];焊接;2003年08期

2 姜幼卿;辜磊;劉建華;;厚板鋁合金YAG-MIG復(fù)合焊接溫度場數(shù)值模擬[J];焊接學(xué)報;2006年06期

3 汪建華，鐘小敏，，戚新海;管板接頭三維焊接變形的數(shù)值模擬[J];焊接學(xué)報;1995年03期

4 蔡洪能，唐慕堯;TIG焊接溫度場的有限元分析[J];機(jī)械工程學(xué)報;1996年02期

5 鹿安理,史清宇,趙海燕,吳愛萍,蔡志鵬,王鵬;焊接過程仿真領(lǐng)域的若干關(guān)鍵技術(shù)問題及其初步研究[J];中國機(jī)械工程;2000年Z1期

相關(guān)碩士學(xué)位論文 前2條

1 畢艷霞;T型接頭焊接溫度場與應(yīng)力場的數(shù)值模擬[D];浙江大學(xué);2007年

2 鄒修興;正交異性鋼橋面焊接應(yīng)力數(shù)值模擬[D];西南交通大學(xué);2012年

本文編號：1430708