【作者】 朱亮；

【导师】 管昌生；

【作者基本信息】 武汉理工大学 ， 结构工程， 2005， 硕士

【摘要】 本文首先对中美英三国关于锅炉钢架柱脚底板的设计方法进行了比较,中国和美国钢结构设计规范的柱脚底板计算的依据是弹性理论,并采取了区格模式分析,从而使得计算的底板厚度较大。而按照英国规范计算的厚度较薄,提出了我国规范中的柱脚底板设计计算方法优化的必要性。 其次,确定了锅炉钢架柱脚底板的构造与计算模型,本文研究的柱脚底板是铰接柱脚形式,它利用柱端与底板的连接焊缝将轴力传递给底板,再由底板分散到基础混凝土上。因此,在计算模型上将基础混凝土作用于柱脚底板的净反力作为底板的外荷载,并将柱端作为底板的支承。应用弹塑性理论建立了柱脚底板挠度方程式,并对柱脚底板应力及挠度进行了分析计算。 在有限元模型中引用了直线单元、中间层无伸缩性、中面的任一法线上各点位移相同、柱脚底板体积不可压缩等假定,简化了计算模型。采用八结点正六面体单元建立了柱脚底板的三维有限元模型,并利用有限元分析程序ANSYS对柱脚底板进行分析计算。柱脚底板的主应力分布图表明,在加载过程中,柱脚底板的翼缘两端首先屈服进入塑性阶段,继续加载,翼缘两端进入塑性极限状态,整个结构宣告破坏。并通过实例,将有限元计算结果与我国规范设计方法的计算结果进行了比较,有限元计算得出的柱脚底板厚度仅为规范计算得出的厚度的60%～70%,这表明锅炉钢架柱脚底板的设计还有较大优化空间。采用本文方法可以优化柱脚底板的设计方法,达到提高计算精确度、优化设计和经济制造的目的。更多还原

【Abstract】 This paper firstly compared with the design method of the column soleplate about boiler steel in China, U.S. and British. Chinese and American calculate basis of design standard of steel structure is flexible theory and have adopted district shelf pattern analysis, which make the calculation thickness of base plate greater. On the contrary, the calculation thickness according to British standard is thinner than the fact. So it is necessarily to put forward the countermeasure against carrying out valuation with bill quantity of construction works.Secondly, it have determined structure and calculation model of the column soleplate in steel boiler. Axial force was transmit to the base plate by the weld connecting column with the soleplate, which is joined with a hinge, and scatter again from base plate to basic concrete. Therefore on the calculating model force in the column soleplate from the basic concrete regard as the outside load of base plate, and column end is the supporting of base plate. The deflection equation of column soleplate has been established according to the elastic- plasticity theory, and has analyses calculation for the deflection and stress of column soleplate.Finite element modeling have quoted the hypothesis of unit of straight line, intermediate layer without flexibility, the same displacement of all nodes in the middle vertical line, and the identical volume of column soleplate cannot compressed, which have simplified calculation model. The three-dimensional finite element modeling of the column soleplate has been established by adopting 8 nodes, straight hexahedron unit. And it also analyses calculation the column soleplate using finite element analysis program ANSYS. The main stress distribution charts of the column soleplate indicate that, in the process of addition loads, the wings of the soleplate of suspension column yield first to give in to enter plasticity stage to enter plasticity stage, then continuing addition load and the wings enter plasticity limit state, so the entire structure announces destroyed. Through the example, the calculation results of finite element design method have been compared with that our country designstandard. The thickness of column soleplate calculating through finite element calculation reach only the 60%~70% of thickness of calculation through the design standard. This shows that the design of the column soleplate in the steel boiler still have greater optimization space. The method of this paper will optimize the design method of the column soleplate to increase the calculate accuracy, optimize design and carry out the bill quantity of production.更多还原