几何缺陷对索拉穹顶弹塑性承载力的影响分析

The Analysis of the Elastoplastic Carrying Capacity of Solar Dome with Geometric Imperfections

摘要: 利用有限元对索拉穹顶进行了特征值屈曲分析，得到了索拉穹顶的屈曲模态，并确定出最不利的屈曲模态阶数。通过讨论几何缺陷形式、大小的变化对结构弹塑性承载力的影响，进一步分析了预应力和杆件截面变化时几何缺陷对弹塑性承载力的影响。分析结果表明：第二阶特征值屈曲模态的缺陷形式对结构最不利；随着拉索预应力的增加，几何缺陷对弹塑性承载力的影响先不变后减小；钢杆件截面改变时，几何缺陷对弹塑性承载力的影响基本不变。

Abstract: Eigenvalue buckling analysis of solar dome was done firstly, then the the buckling modes were got and the most unfavorable mode was pointed. The influence factors of bearing capacity, such as the form and bigness of geometric defect, were discussed. The influence of prestress and the section of rod was further studied. The result shows: The second-order buckling mode is the most unfavorable mode; as the prestress of rop grows, the influence of geometric defect to elastoplastic carrying capacity increases firstly and then decreases; as the section of rod changes, the influence of geometric defect to elastoplastic carrying capacity essentially unchanged.