基于响应面的桥梁有限元模型修正
- 格式:pdf
- 大小:524.12 KB
- 文档页数:8
梁式桥梁有限元模型建立与修正及在状态评估中的应用研究的开题报告一、题目:梁式桥梁有限元模型建立与修正及在状态评估中的应用研究二、研究意义和背景:近年来,世界上许多桥梁的年限已经接近了设计寿命,加之大气污染、自然灾害等因素的影响,桥梁的健康状态变得越来越受到关注。
在桥梁的设计、施工和使用阶段,对桥梁的状态进行评估,以便及时发现和解决各种问题,是非常重要的。
而现代结构工程中使用最为广泛的是有限元方法,对桥梁进行有限元模型的建立和修正,可以为之后的状态评估提供帮助。
然而,在建立和修正有限元模型时,往往会存在一些误差和偏差,这会导致状态评估结果的不准确和不可靠。
因此,有必要对梁式桥梁的有限元模型建立和修正进行深入研究,并探索其在桥梁状态评估中的应用。
三、研究内容:本研究拟围绕梁式桥梁的有限元模型建立和修正,以及在桥梁状态评估中的应用为主要内容,具体研究内容包括但不限于以下方面:1. 梁式桥梁的有限元模型建立方法,包括杆件单元和板单元的使用、节点分布和网格生成等方面的问题。
2. 梁式桥梁有限元模型的修正方法,包括传统修正和基于监测数据的修正方法。
3. 梁式桥梁状态评估方法,包括结构健康监测、激励响应分析和可靠度分析等方面的问题。
4. 基于梁式桥梁有限元模型的状态评估实例研究,包括模型建立、修正和状态评估的完整流程。
四、研究方法:本研究主要采用实验研究和理论研究相结合的方法,具体包括:1. 对已建造的梁式桥梁进行实际监测,获取其相应的响应数据。
2. 在有限元软件中建立梁式桥梁的有限元模型,并与实际监测数据进行对比,修正模型并评估修正效果。
3. 基于修正后的有限元模型,进行激励响应分析和可靠度分析,并对结果进行分析和解释。
4. 针对具体的梁式桥梁,通过整合前述实验和理论研究成果,构建其完整的状态评估体系。
五、研究预期成果:本研究预期可以达到以下目标:1. 建立基于杆件单元和板单元的梁式桥梁有限元模型建立方法,并提出调整和优化方案。
基于响应面的大型输电塔结构有限元模型动力修正程霄翔;费庆国;何顶顶;韩晓林【摘要】针对基于灵敏度分析的有限元模型动力修正方法计算效率较低、迭代收敛慢的不足,将响应面法引入500 kV大跨越输电塔基准模型修正.选择塔脚弹性支承刚度为修正参数,依次进行单因素试验、样本值计算、响应面建立与分析、参数优化.修正后,有限元模型非常准确地复现了单塔横、纵两个方向的-阶弯曲动态特性,修正效果与基于灵敏度分析的模型修正方法接近,证明响应面法在有限元模型动力修正领域的应用价值.还探讨了塔架结构修正参数的选取问题,为相关研究提供参考.%To conquer deficiencies of poor computational efficiency and slow convergence of traditional sensitivity analysis-based finite element (FE) model updating methodology used widely, response surface methodology was introduced into a 500kV large transmission tower's dynamic FE model updating. Based on authors' former contributions,elastic stiffnesses of the tower's three directional foot bearings were selected as parameters to be updated. Key steps in updating process including one factor test, sample on FE platform, building and analyzing response surface and parameter optimization were presented in succession, then response surface-based dynamic FE model updating was completed. The updated tower model accurately recurred the structure's primary and secondary natural frequencies, and its effect was close to that of the sensitivity analysis-based methodology, its application value was proved. The problem of parameter selection for model updating of pylon structures was also explored.【期刊名称】《振动与冲击》【年(卷),期】2011(030)005【总页数】7页(P116-122)【关键词】模型修正;响应面法;大型输电塔;参数选取;动态特性【作者】程霄翔;费庆国;何顶顶;韩晓林【作者单位】东南大学,土木工程学院,南京,210096;东南大学,土木工程学院,南京,210096;东南大学,土木工程学院,南京,210096;东南大学,土木工程学院,南京,210096【正文语种】中文【中图分类】TU347有限元模型修正是一个通过逐步修正模型参数使得有限元计算结果与测试值尽可能接近的迭代优化过程,目前针对大型工程结构的有限元模型修正通常基于灵敏度分析。
基于响应面法的印制电路板组件有限元模型修正王开山;李传日;庞月婵;郭恒晖【摘要】Onthepremiseoftakingthematerialsoftheprintedcircuitboardanditscompone ntsasorthotropic,a method based on response surface was proposed to update the finite element model (FEM) of printed circuit board assembly(PCBA).The parameters which have great influence on the modal frequencies of PCBA were screened out and taken as the updating parameters by correlation analysis.The sample points were acquired by using an appropriate experimental design according to the number of the updating parameters to construct a polynomial response surface model. The least squares method was used to determine the polynomial coefficients and then to test the fitting accuracy of response surface.The absolute value of error between the result of the calculated response surface and that of an actual test was taken as an objective function.The optimized parameters were obtained taking advantage of the iterative calculation of the multiple objectives genetic algorithm (MOGA ).The updated model was then obtained by substituting the optimized parameters into the non-updated FEM.Taking the PCBA of an aircraft electronic product as an example,the comparison between the modal frequencies of non-updated and updated FEM shows that the relative error of modal frequencies of the updated FEM to the actual test is obviously reduced and thus verifies the effectiveness of the model updatingmethodology suggested.%在将印制电路板及元器件材料视为正交各向异性前提下,提出基于响应面法的印制电路板组件(Printed Circuit Board Assembly,PCBA)有限元模型修正法。
基于响应面方法的多喷嘴引射器有限元模型修正杨毅晟;刘宗政;麻越垠;闫喜强;王元兴;谢强【摘要】针对某多喷嘴引射器在脉动载荷作用下的动力学响应预测问题,对其有限元模型进行了修正,减少了材料属性、边界条件等对计算结果的影响.首先开展了引射器有限元模态分析,获得了初始模态分析频率;采用了多点激励多点响应锤击法进行了模态试验,获取了试验模态频率;基于有限元模型进行了误差分析,确定了材料密度、弹性模量、质量点质量等修正参数,通过中心复合设计方法确定了样本空间,构建了多目标响应面并对待修正参数进行了约束优化,得到了修正参数的最优解;最后,使用修正后的参数进行了有限元分析,获得了修正后的模态分析频率,并通过动力响应计算进行了模型确认.研究结果表明:修正后模态分析频率与模态试验频率(前三阶)误差均值由修正前的8.01%减小到2.81%,该修正方法能够显著提高有限元模态分析精度.%Aiming at the problems that prediction of the dynamic response of a multi-nozzle ejector under the action of pulsating load, the fi-nite element model was updated to reduce the influence of material properties and boundary conditions on the calculation results. Firstly, the finite element modal analysis of the ejector was carried out to obtain the initial modal analysis frequency. Secondly, the hammering modal test on ejector was done using multi-input multi-output analysis method to get the modal test frequency of ejector. Thirdly, based on the finite ele-ment model error analysis, the correction parameters such as material density, elastic modulus and quality of mass-point were determined. After the sample space was determined by the central composite design method, the multi-objective response surface was constructed and used to obtainthe optimal solution of the correction parameters. Finally, the optimal correction parameters were used for finite element analysis to obtain the corrected modal analysis frequency and dynamic response under the real load. The results indicate that the error of the first three modes between the corrected modal analysis frequency and the modal test frequency is reduced from 8. 01% to 2. 81%, so the updating method can significantly improve the precision of the finite element modal analysis.【期刊名称】《机电工程》【年(卷),期】2017(034)012【总页数】6页(P1376-1381)【关键词】多喷嘴引射器;响应面;模态试验;模态分析;模型修正【作者】杨毅晟;刘宗政;麻越垠;闫喜强;王元兴;谢强【作者单位】中国空气动力研究与发展中心,四川绵阳621000;中国空气动力研究与发展中心,四川绵阳621000;中国空气动力研究与发展中心,四川绵阳621000;中国空气动力研究与发展中心,四川绵阳621000;中国空气动力研究与发展中心,四川绵阳621000;中国空气动力研究与发展中心,四川绵阳621000【正文语种】中文【中图分类】TH113.1;TB123近年来,有限元法已经成为模态分析领域的支柱方法之一。
现代机械设计理论与方法有限元方法学院:机械工程学院日期:2012年12月8日目录摘要 (3)关键词 (3)Abstract (3)Key Words (4)1 有限元方法的国内外研究现状及应用实例 (4)1.1 有限元的发展趋势 (4)1.2 有限元的应用实例 (4)2 有限元方法的分析过程 (5)2.1 有限元分析的三个阶段 (5)2.2 有限元分析的七个步骤 (5)2.3 有限元软件的分析过程 (6)3 参考文献 (8)有限元方法摘要:有限元方法法的基本概念是用较简单的问题代替复杂问题后再求解。
有限元法的基本思想是先化整为零﹑再积零为整,也就是把一个连续体分割成有限个单元;即把一个结构看成由若干通过节点相连的单元组成的整体,先进行单元分析,然后再把这些单元组合起来代表原来的结构进行整体分析。
关键词:有限元方法;单元;节点Finite Element MethodAbstract:The basic concepts of the finite element method is solving complex problems with a simple question instead.The basic idea of the finite element method is dismembered, and then plot the parts into a whole, that is divided a continuum into a finite number of unit; that is to regard a structure as a whole connected by many nodes,first to analysis unit,then analysis the overall combined by these units,which represents the original structure.Key Words:finite element method;unit;node1 有限元方法的国内外研究现状及应用实例“有限单元法”这一名称是克拉夫(Clough)在1960年首先引用的。