液压顶升平桥动态特性研究

发布时间：2018-04-27 23:46

本文选题：液压顶升平桥 + 动态特性　；参考：《东北大学》2012年硕士论文

【摘要】：随着世界对能源需求的急剧增长,用于冷却循环水的大型冷却塔越来越大,塔体也越来越高,高达180m以上。本课题为“十一五”规划课题,主要以国内冷却塔专用施工设备—液压顶升平桥为研究对象,研究其动态特性及编制柔性附着计算软件。利用有限元软件ANSYS,对处于独立高度且无柔性附着的液压顶升平桥进行建模。通过平桥载荷特性曲线确定静力计算工况,通过应力比较确定最危险工况,其应力与应力测试结果相吻合,验证平桥的有限元模型的正确性；并且利用ANSYS软件对液压顶升平桥进行动力学分析,计算不同起升速度的起升动载荷系数。当起升速度在某范围内,动载荷系数随起升速度的增加而显著增大；超过该范围,动载荷系数变化较平缓。根据对3种典型工况的计算分析,通过应力比较,确定出吊重离地起升与回转复合工况最危险,其最大应力是静力分析时应力的1.5倍左右,为平桥的初步设计和动态特性研究提供技术支持。当平桥桥身高度超过独立高度时,为保证桥身的结构稳定与工作平稳,须采用多层带有预拉力的钢丝绳加以柔性附着。将液压顶升平桥的桥身与附着钢丝绳作为桥身系统来考虑。采用ANSYS软件对2层附着的桥身系统进行静动力学分析,动力分析计算的最大应力约为静力时应力的2.4倍,桥身顶端的位移是静力时位移的7倍左右,且附着钢丝绳的拉力也有所增加。因此,对桥身系统进行动力学分析是非常必要的。根据柔性附着的分析与计算,以VB6.0和Matlab7.0作为程序设计语言,并动态连接Excell2003及Acess2003,开发柔性附着计算软件。该软件具有数值计算、曲线绘图、保存、查找、删除、打印及生成报表等功能。此软件为平桥柔性附着专用计算软件,开创了柔性附着计算软件编制的先河,方便设计者设计计算,减小设计工作量,缩短设计周期,对平桥的设计起到了积极促进作用。
[Abstract]:With the rapid increase of energy demand in the world, the large cooling tower used for cooling circulating water is becoming larger and larger, and the tower body is more and more high, up to more than 180m. This subject is the "11th Five-Year Plan" project, mainly takes the domestic cooling tower special construction equipment-hydraulic jacking flat bridge as the research object, studies its dynamic characteristic and compiles the flexible attachment calculation software. The finite element software ANSYSwas used to model the hydraulic jacking flat bridge with independent height and no flexible attachment. The static calculation condition is determined by the load characteristic curve of the horizontal bridge and the most dangerous condition is determined by the stress comparison. The results of the stress and stress test are in agreement with each other, which verifies the correctness of the finite element model of the horizontal bridge. The dynamic analysis of hydraulic jacking bridge is carried out by using ANSYS software, and the lifting load coefficient of different lifting speed is calculated. When the lifting speed is in a certain range, the dynamic load coefficient increases significantly with the increase of the lifting speed, and the change of the dynamic load coefficient is slower than that of the rising speed. According to the calculation and analysis of the three typical working conditions, through the stress comparison, it is determined that the composite working condition of hoisting and rotary hoisting is the most dangerous, and the maximum stress is about 1.5 times of the stress in static analysis. It provides technical support for the preliminary design and dynamic characteristic study of the flat bridge. When the height of the bridge body is higher than the independent height, in order to ensure the stability and stability of the bridge body, the multi-layer wire rope with pretension should be used for flexible attachment. The bridge body and attached wire rope of hydraulic jacking flat bridge are considered as bridge body system. The static and dynamic analysis of the two-story attached bridge system is carried out by using ANSYS software. The maximum stress calculated by dynamic analysis is about 2.4 times of the static stress, and the displacement at the top of the bridge is about 7 times that of the static displacement. The tensile force of the attached wire rope is also increased. Therefore, the dynamic analysis of bridge system is very necessary. According to the analysis and calculation of flexible attachment, the flexible attachment calculation software is developed by using VB6.0 and Matlab7.0 as programming languages and connecting Excell2003 and Acess 2003 dynamically. The software has the functions of numerical calculation, curve drawing, saving, searching, deleting, printing and generating reports. This software is a special calculation software for flexible attachment of flat bridges, which is the first to compile flexible attachment calculation software. It is convenient for designers to design and calculate, reduces the workload of design, shortens the design period, and plays an active role in promoting the design of flat bridges.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH21;TH137

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