水平弹性支承圆弧钢拱的几何非线性稳定研究  

Study for geometric non-linear stability of steel circular arches with horizontal spring supports

作　　者：黄山[1] 杨洋 

机构地区：[1]浙江大学建筑设计研究院,杭州310028 [2]浙江绿城东方建筑设计有限公司,杭州310012

出　　处：《建筑结构》2013年第15期131-135,141,共6页Building Structure

摘　　要：钢拱常支承于其他结构上,拱脚在水平方向很难做到完全的刚性支承,拱的支座约束可以用拱脚处的水平弹簧进行等效替代。利用ANSYS有限元程序,采用大挠度变形理论对水平弹性支承拱进行了研究,分析了其平面内屈曲模态和失稳特征,对影响失稳的支座约束刚度、长细比、圆心角和几何初始缺陷等因素进行了深入的探讨。通过构造反映支座约束程度的弹性柔度系数,拟合得到了非线性极限荷载及支座水平位移的计算表达式,并具有良好的精度。理论分析结果表明,在工程设计中应考虑支座约束对拱的影响,并可以利用弹性柔度系数对承载力和支座位移进行定量分析。Arches which are supported by other structural members can be considered to be supported elastically at both ends by horizontal springs. An elastic finite element model was established to study the in-plane modes of buckling and characteristic of stability of steel circular arches with horizontal spring supports using large deformation theory by ANSYS. The effects of stiffness of the horizontal end restraints, slenderness, angle and geometric initial defect on the stability of arches with I-sections are investigated. A dimensionless elastic softness factor which respects the restraint of supports is advanced. Based on the numerical results, formulas with good accuracy for non-linear ultimate load and displacement of supports under ultimate strength in terms of the stiffness of ends are proposed. It is pointed out that stiffness of the horizontal end restraints shall not be neglected in the engineering design, and ultimate load and displacement of supports can be calculated by elastic flexibility factor.

关 键 词：圆弧拱 几何非线性 屈曲模态 极限荷载 弹性约束 

分 类 号：TU311.2[建筑科学—结构工程]