单轴对称截面圆弧拱弹性弯扭屈曲临界荷载  

Elastic Flexural-torsional Buckling Load of Monosymmetric Circular Arches

作　　者：窦超[1] 郭彦林[1] 

机构地区：[1]清华大学土木工程系,北京100084

出　　处：《建筑科学与工程学报》2011年第4期69-74,85,共7页Journal of Architecture and Civil Engineering

基　　金：国家自然科学基金项目(50478013)

摘　　要：为了研究均布径向压力作用下的单轴对称截面均匀受压圆弧拱的弹性弯扭屈曲临界荷载,为一般荷载作用下压弯钢拱的稳定承载力设计奠定基础,采用平衡法推导得到了均匀受压圆弧拱的面外屈曲临界荷载的理论解。在微元段受力平衡的基础上,建立了任意轴线形状、截面形式的曲线构件的平衡方程,代入截面变形条件、内力与变形条件推导出了单轴对称截面均匀受压两端铰支圆弧拱的屈曲方程,求解得到了保向分布力作用下的弯扭屈曲临界荷载。采用ANSYS有限元数值方法进行了分析比较,研究了截面不对称性、荷载作用位置对弹性弯扭屈曲临界荷载的影响。结果表明:所提出的平衡法推导过程概念清晰明确,所得解析解与有限元数值解吻合较好,具有较高的精度。To study the elastic flexural-torsional buckling load of monosymmetric circular arches under uniform radial pressure which can be used in the design of stable bearing capacity of steel arches under both compression and bending, the theoretical solution for out-of-plane buckling loads of monosymmetric circular arches under uniform compression was obtained by using equilibrium method. Based on the force equilibrium of curve infinitesimal, equilibrium equations for curved members with any axial form and section form were established. Combined with sectional deformation equations, relations between inner forces and deformation, the buckling equations of two-hinged monosymmetric circular arches under uniform compression and flexuraltorsional buckling loads under distribution forces were derived and obtained. ANSYS finite element numerical method was adopted for analysis and comparison, and the influence of sectional asymmetry and loading position on elastic flexural-torsional buckling load was investigated. The results show that the the derivation procedure used in the paper is clear and definite, and the obtained analytical solution of buckling load is coincided well with the finite element numerical answer, and it has a high accuracy.

关 键 词：钢拱 弯扭屈曲 平衡法 屈曲临界荷载 荷载作用位置 圆弧拱 

分 类 号：TU32[建筑科学—结构工程]