全跨和半跨荷载组合下两铰抛物线钢拱承载力计算方法对比
发布时间:2018-07-25 13:35
【摘要】:钢拱结构是建筑结构的一种常见的结构形式,广泛地应用于大跨度钢结构。当钢拱结构破坏时,人们的生命财产会受到严重损失,故而对钢拱结构进行设计研究是很有必要的。本文首先运用ANSYS有限元方法对完善钢拱结构进行屈曲模态分析,建立了一致缺陷钢拱结构模型。同时,对所建立的两铰抛物线完善与一致缺陷钢拱结构进行线弹性计算结果对比分析,包括荷载效应系数的对比和刚度对比,随后进行了二阶效应的分析,比较了两种钢拱结构二阶分析时的应力的变化情况,最后对两种钢拱结构进行受力全过程分析。全跨和半跨荷载组合下,钢拱结构的内力分布通常会随着荷载组合比例发生较大的变化,现有钢拱结构平面内稳定承载力计算式多是针对单一加载模式分析得到的,对于钢拱结构在全跨和半跨组合荷载下的分析比较缺乏。针对此不足,本文考虑荷载组合比例、截面、矢跨比等不同的参数影响建立了两铰抛物线钢拱结构模型,对比分析了现行钢拱结构技术规程建议的方法、日本学者Kuranishi和Yabuki提出的方法、基于完善钢拱模型有限元方法、基于一致缺陷钢拱结构模型的有限元方法和考虑二阶效应的强度设计方法等五种方法的极限承载力计算结果。结果分析表明,不同方法的极限承载力结果差异很大;在参数分析的范围内,当半跨荷载占较大比重时,规程方法计算的极限承载力比其他四种方法计算的极限承载力大,使规程方法设计钢拱结构偏于不安全;而当全跨荷载占较大比重时,规程方法计算的极限承载力比其他四种方法计算的极限承载力小,使规程方法设计钢拱结构偏于保守。我国《拱形钢结构技术规程》(JGJ/T 249-2011)和日本学者Kuranishi和Yabuki提出的方法对所建立的两铰抛物线钢拱结构进行内力的分析,得到了其轴力与弯矩的设计曲线的比较图,由图可以看出此两种方法内力和承载力的差异。
[Abstract]:Steel arch structure is a common structural form of building structure, which is widely used in long span steel structure. When the steel arch structure is destroyed, people's life and property will be seriously lost, so it is necessary to design and study the steel arch structure. In this paper, ANSYS finite element method is used to analyze the buckling mode of steel arch structure, and a uniformly defective steel arch structure model is established. At the same time, the linear elastic calculation results of the two hinged parabola perfect and consistent defect steel arch structures are compared and analyzed, including the comparison of load effect coefficient and stiffness, and then the second order effect is analyzed. The stress changes of two kinds of steel arch structures during the second order analysis are compared. Finally, the stress process of the two kinds of steel arch structures is analyzed. Under the combination of full span and half span load, the internal force distribution of steel arch structure usually changes greatly with the ratio of load combination. The existing calculation formulas of in-plane stability bearing capacity of steel arch structure are mostly based on the analysis of single loading mode. The analysis of steel arch structure under full span and half span combined loads is scarce. In view of this deficiency, considering the influence of different parameters such as load combination ratio, cross section and rise-span ratio, this paper establishes a two-hinge parabolic steel arch structure model, and compares and analyzes the methods suggested by the current technical specification for steel arch structure. The methods proposed by Japanese scholars Kuranishi and Yabuki are based on the finite element method of perfect steel arch model, the finite element method of uniformly defective steel arch structure model and the strength design method considering second-order effect. The results show that the results of ultimate bearing capacity of different methods are very different, and in the range of parameter analysis, the ultimate bearing capacity calculated by the regulation method is larger than that calculated by the other four methods when the half span load takes up a large proportion of the total load. The design of steel arch structure by regulation method is not safe, but the ultimate bearing capacity calculated by regulation method is smaller than that calculated by other four methods when the total span load is larger than that calculated by other four methods, which makes the design of steel arch structure by regulation method more conservative. The Technical Specification for Arch Steel structures (JGJ/T 249-2011) and the methods proposed by Japanese scholars Kuranishi and Yabuki are used to analyze the internal forces of the two-hinged parabola steel arch structures, and a comparative diagram of the design curves of the axial force and bending moment is obtained. The difference of internal force and bearing capacity between the two methods can be seen from the diagram.
【学位授予单位】:长沙理工大学
【学位级别】:硕士
【学位授予年份】:2014
【分类号】:TU393.3
本文编号:2143984
[Abstract]:Steel arch structure is a common structural form of building structure, which is widely used in long span steel structure. When the steel arch structure is destroyed, people's life and property will be seriously lost, so it is necessary to design and study the steel arch structure. In this paper, ANSYS finite element method is used to analyze the buckling mode of steel arch structure, and a uniformly defective steel arch structure model is established. At the same time, the linear elastic calculation results of the two hinged parabola perfect and consistent defect steel arch structures are compared and analyzed, including the comparison of load effect coefficient and stiffness, and then the second order effect is analyzed. The stress changes of two kinds of steel arch structures during the second order analysis are compared. Finally, the stress process of the two kinds of steel arch structures is analyzed. Under the combination of full span and half span load, the internal force distribution of steel arch structure usually changes greatly with the ratio of load combination. The existing calculation formulas of in-plane stability bearing capacity of steel arch structure are mostly based on the analysis of single loading mode. The analysis of steel arch structure under full span and half span combined loads is scarce. In view of this deficiency, considering the influence of different parameters such as load combination ratio, cross section and rise-span ratio, this paper establishes a two-hinge parabolic steel arch structure model, and compares and analyzes the methods suggested by the current technical specification for steel arch structure. The methods proposed by Japanese scholars Kuranishi and Yabuki are based on the finite element method of perfect steel arch model, the finite element method of uniformly defective steel arch structure model and the strength design method considering second-order effect. The results show that the results of ultimate bearing capacity of different methods are very different, and in the range of parameter analysis, the ultimate bearing capacity calculated by the regulation method is larger than that calculated by the other four methods when the half span load takes up a large proportion of the total load. The design of steel arch structure by regulation method is not safe, but the ultimate bearing capacity calculated by regulation method is smaller than that calculated by other four methods when the total span load is larger than that calculated by other four methods, which makes the design of steel arch structure by regulation method more conservative. The Technical Specification for Arch Steel structures (JGJ/T 249-2011) and the methods proposed by Japanese scholars Kuranishi and Yabuki are used to analyze the internal forces of the two-hinged parabola steel arch structures, and a comparative diagram of the design curves of the axial force and bending moment is obtained. The difference of internal force and bearing capacity between the two methods can be seen from the diagram.
【学位授予单位】:长沙理工大学
【学位级别】:硕士
【学位授予年份】:2014
【分类号】:TU393.3
【参考文献】
相关期刊论文 前1条
1 林冰;郭彦林;黄李骥;;均匀受压两铰圆弧钢拱的平面内稳定设计曲线[J];工程力学;2008年09期
,本文编号:2143984
本文链接:https://www.wllwen.com/guanlilunwen/chengjian/2143984.html