混凝土两铰圆弧拱的面内徐变稳定性  

IN-PLANE CREEP BUCKLING OF PIN-ENDED CONCRETE CIRCLE ARCHES

作　　者：蒋伟[1] 吕大刚[1] 

机构地区：[1]哈尔滨工业大学土木工程学院,哈尔滨150090

出　　处：《工程力学》2012年第A02期186-189,共4页Engineering Mechanics

摘　　要：结合两铰圆弧拱的面内屈曲微分方程和混凝土徐变的Arutyunyan-Maslov方程,并引入徐变积分算子和失稳条件推导了混凝土两铰圆弧拱的面内徐变临界力计算公式。基于该公式,通过算例讨论了徐变系数和截面含钢率对徐变临界力的影响,并对素混凝土拱、钢筋混凝土拱和钢管混凝土拱的徐变临界力进行了对比。结果表明:对于不同拱肋材料,混凝土徐变均会导致临界力的降低;由于材料组成的差别,徐变对素混凝土拱临界力的影响最大,钢筋混凝土拱次之,而对钢管混凝土拱的影响最小;与已有方法相比,该公式反映了截面配筋率或含钢率对徐变临界力的影响。The in-plane buckling differential equation of pin-ended circle arches and Arutyunyan-Maslov （AM） creep law are combined, and the creep integral operator and instability condition are introduced to derive the formula for the creep buckling strength of pin-ended concrete circle arches. Based on the formula, the influences of the creep coefficient and steel ratio are discussed via a numerical example. The creep buckling strength of plain concrete （PC） arches, reinforced concrete （RC） arches and concrete-filled steel tubular （CFST） arches are comparatively analyzed. The results show that creep buckling strength decreases with time for different material compositions of arch ribs. The concrete creep has a great effect on the stability of PC arches followed by RC arches and CFST arches. Compared with the existing method, the AM-based formula could reflect the influence of the steel ratio on a creep buckling.

关 键 词：两铰圆弧拱 徐变稳定性 公式推导 混凝土拱 长期荷载 

分 类 号：TU311.2[建筑科学—结构工程]