單斜塔斜拉橋主塔提升受力分析

摘  要
本文以天津市泰達(dá)天橋——單斜塔斜拉橋?yàn)楸尘埃芯繂涡彼崩瓨蛑魉嵘氖芰η闆r。整個(gè)課題的研究過程采用了有限元的分析方法，利用工程分析軟件ANSYS進(jìn)行建模求解。
首先根據(jù)設(shè)計(jì)圖紙建立該橋完整的初始空間有限元模型，并根據(jù)設(shè)計(jì)內(nèi)容的要求施加自重和相應(yīng)的風(fēng)荷載，然后求解并對(duì)提升系統(tǒng)在提升到不同角度時(shí)的反力、位移和應(yīng)力等進(jìn)行理論分析以確保主塔提升過程的安全可靠。根據(jù)受力情況塔架采用了Link8和Beam4兩種單元，主塔采用了Shell63單元，索采用了Link10單元。計(jì)算結(jié)果表明單元的選取都是合理的；應(yīng)力的最值出現(xiàn)在提升索和主塔的連接處，存在應(yīng)力集中的現(xiàn)象，在排除了局部應(yīng)力集中的情況下，整個(gè)提升過程安全可靠，因此，在施工過程中對(duì)局部應(yīng)力集中處采取有效的加固措施顯得至關(guān)重要；結(jié)果分析顯示提升索力的變化是非線性的，提升起始階段的索力較大，隨后索力不斷減小，接近提升終止時(shí)，提升索力又變大。提升索的最大索力為2150kN，出現(xiàn)在提升的終止階段；變形最大的點(diǎn)一般出現(xiàn)在吊梁的中點(diǎn)附近，但并未超出允許值。

關(guān)鍵詞：?jiǎn)涡彼?nbsp; 斜拉橋  有限元分析  提升過程

 
Abstract
Tianjin Taida flyover, a single skew tower cable-stayed bridge is used as the background in this paper. The stress of the main tower of cable-stayed bridge with single skew tower during its hoisting process is researched here. The whole design process uses the finite element method and uses ANSYS, an engineering analysis software, to mode and solve.
The initial space finite element model of the bridge is established firstly, according to its drawings. At the same time, the dead weight of the bridge and the corresponding wind loads are also imposed on the bridge according to the design requirements. Then reaction force, displacement and stress are analyzed when the system is enhanced to different angles in order to ensure the safety and reliability of the main tower during its whole hoisting process. The tower frame uses two elements, Link8 and Beam4, according to the force conditions. The main tower uses the Shell63 element and the cables use the Link10 element. The results prove that the selections of these elements are reasonable. The biggest value of the stress is at the connection of the main tower and the lifting-cable, where exists the phenomenon of stress concentration. The hoisting process is safe and reliable when the local stress concentration is eliminated. So it is very important to strengthen the positions of the local stress concentration during the construction process. The change of the lifting-cable tension is nonlinear showed by the results. The value is larger at the beginning of the lifting process and it decreases during the process. The value of the lifting-cable tension turns larger again when the whole process is close to the end. The biggest value is 2150 kN and it happens at the end of the process. The point which happens the greatest deformation is always at the midpoint of the hanging beam and it does not exceed the allowable value. 

Key words: Single Skew Tower   Cable-Stayed Bridge   Finite Element Analysis Hoisting Process
 
目  錄
第1章  緒論 1
1.1  課題研究的目的意義 1
1.2  國內(nèi)外研究現(xiàn)狀 1
1.2.1  斜拉橋的發(fā)展現(xiàn)狀 1
1.2.2  轉(zhuǎn)體施工的研究現(xiàn)狀 2
1.3  論文研究?jī)?nèi)容簡(jiǎn)介 2
1.4  論文主要研究?jī)?nèi)容和研究方法 3
1.5  論文研究方法及創(chuàng)新點(diǎn) 3
第2章  提升塔架的力學(xué)研究 5
2.1  提升塔架結(jié)構(gòu)計(jì)算書 5
2.1.1  提升塔架結(jié)構(gòu)簡(jiǎn)介 5
2.1.2  提升塔架基礎(chǔ)結(jié)構(gòu)受力分析 5
2.1.3  提升塔架基礎(chǔ)強(qiáng)度計(jì)算 5
2.2  管撐的構(gòu)造力學(xué)計(jì)算 6
2.3  分配梁L1、L2的力學(xué)構(gòu)造計(jì)算 7
2.4  吊梁的結(jié)構(gòu)力學(xué)計(jì)算 7
第3章  有限元模型的建立 9
3.1  有限元分析過程簡(jiǎn)介 9
3.1.1  有限元系統(tǒng)基本構(gòu)成 9
3.1.2  ANSYS有限元分析過程 9
3.2  實(shí)體建模的建立 10
3.2.1  前言 10
3.2.2  建立實(shí)體模型 11
3.3  材料設(shè)置與網(wǎng)格劃分 13
3.3.1  前言 13
3.3.2  Element Type確定單元類型 13
3.3.3  幾何模型網(wǎng)格劃分 15
3.4  總結(jié) 17
第4章  加載與求解 18
4.1  簡(jiǎn)介 18
4.1.1  荷載定義及分類 18
4.1.2  實(shí)體模型載荷與有限元模型載荷的優(yōu)缺點(diǎn) 19
4.1.3  可能出現(xiàn)的問題 20
4.2  提升塔架的風(fēng)荷載計(jì)算規(guī)范 20
4.2.1  風(fēng)荷載 20
4.2.2  風(fēng)荷載的計(jì)算 20
4.2.3  計(jì)算風(fēng)壓q 21
4.2.4  風(fēng)壓高度變化系數(shù)Kh 21
4.2.5  風(fēng)力系數(shù)C 22
4.2.6  迎風(fēng)面積A 22
4.3  起重塔架的風(fēng)荷載計(jì)算過程 24
4.3.1  1-20m的風(fēng)荷載計(jì)算 24
4.3.2  20-40m的風(fēng)荷載計(jì)算 25
4.4  單斜塔的風(fēng)荷載計(jì)算規(guī)范 25
4.4.1  風(fēng)荷載標(biāo)準(zhǔn)值及基本風(fēng)壓 25
4.4.2  風(fēng)壓高度變化系數(shù) 26
4.4.3  風(fēng)荷載體型系數(shù) 26
4.4.4  風(fēng)振系數(shù) 27
4.5  單斜塔風(fēng)荷載的計(jì)算過程 27
4.6  附錄 29
4.7  總結(jié) 29
第5章  結(jié)果數(shù)據(jù)的分析 30
5.1  后處理器簡(jiǎn)介 30
5.2  結(jié)果的圖形和列表顯示 30
5.2.1  提升角度為9° 30
5.2.2  提升角度為20° 36
5.2.3  提升角度為30° 42
5.2.4  提升角度為40° 46
5.2.5  提升角度為46° 51
5.3  結(jié)果分析 55
5.4  結(jié)論 56
第6章  結(jié)果數(shù)據(jù)的列表顯示 57
6.1  反力列表 57
6.2  最大位移列表 57
6.3  提升索和平衡索的軸力和軸向應(yīng)力列表 58
6.4  最大應(yīng)力列表 58
6.5  結(jié)論 58
第7章 結(jié)論與展望 60
7.1  結(jié)論 60
7.2  展望 61
參考文獻(xiàn) 62
致謝 63
附錄 64