基于有限元模型修正技术的复杂索拱体系施工稳定性
2018-03-21戴轩奥张其林罗晓群
戴轩奥 张其林 罗晓群
摘要:为准确分析复杂索拱体系结构的施工稳定性,以山东淄博潭溪山桥为例,提出一种基于有限元模型修正技术的分析方法。建立包括细部构造的精细化有限元模型,以节点位移构造目标函数对简化的梁系模型进行静力修正,修正后的梁系模型位移结果得到小幅改进,索力和结构应力得到明显改进。分别计算施工过程各阶段修正模型与未修正模型的线性稳定安全因数与非线性稳性定安全因数,对比分析结果认为:修正模型能够体现实际细部构造的加强作用,可使分析更为精确。将修正模型的稳定性分析结果与规范对比,认为结构施工稳定性满足要求。
关键词:有限元; 修正; 全过程; 线性稳定; 非线性稳定; 安全因数
中图分类号:U445.35; O242.1
文献标志码:B
文章编号:1006-0871(2018)01-0035-07
Abstract: To accurately analyze the construction stability of complex structure with arch and cable, an analysis method based on finite element model updating method is presented taking Tanxishan Bridge in Shandong Province as a case. The refine finite element model including detailed structures is built, and the objective function on node displacement is adopted to update the static forces of the simplified beam system model. The displacement results of beam system model is improved slightly, and the cable force and structural stress is improved obviously. The safety factors of linear stability and nonlinear stability on every stage of construction process are compared between the initial model and the updating model. The analysis results show that the reinforce of the actual detail structures can be expressed using the updating model, and the analysis is more accurate. The stability analysis results comparison between updating model and the standard shows that the construction stability meets the requirements.
Key words: finite element; updating; whole process; linear stability; nonlinear stability; safety factor
0 引 言
随着社会经济文化的日益发展,桥梁结构不仅要具备使用价值,还要兼备美学价值。以索拱体系为结构框架的桥梁能够形成灵活的空间布置,创造出优美独特的外形,因此被广泛认可。然而,索拱体系桥梁外观常突破常规,其结构也变得更加复杂,其施工过程中的稳定性问题是结构分析的重点。随着有限元技术的发展,有限元分析可以在此类结构分析中发挥重要作用。对于复杂的索拱体系桥梁,传统的空间梁系模型由于隐含较多理想化假定或简化,与结构的实际状况存在较大差异,因此结果存在较大误差。[1]为更加准确地分析此类……
