I型裂纹对薄壁偏心柱弹性挠度的影响  

Influence of crack on elastic deflection of eccentric thin-walled column

作　　者：周利[1] 

机构地区：[1]五邑大学土木工程系,广东江门529020

出　　处：《计算力学学报》2001年第2期216-220,共5页Chinese Journal of Computational Mechanics

摘　　要：本文重点研究了裂纹对薄壁截面偏心受压柱弹性挠度的影响。分析模型假设偏心柱两端铰支 ;截面绕强轴发生单向弯曲变形 ;I型裂纹位于受力最为严重的中间截面内的受拉翼缘上。首先简单介绍了由 Rayleigh- Ritz变分法求得的弹性挠度三角函数级数解 ,该解的优点是可以在裂纹截面满足变形协调条件 ,适应于裂纹在薄壁截面上沿弯矩面外方向扩展的情况。然后针对工字形、箱形两种双轴对称薄壁截面柱 ,具体地分析了在不同荷载、偏心距和长细比条件下裂纹长度对偏心柱挠度的影响规律和范围。理论分析和数值结果表明 :在其它条件不变的情况下 ,柱的长细比越小或偏心距越大 ,裂纹引起的挠度增量越明显。The influence of crack on elastic deflection of eccentric thin\|walled column with both ends pinned was studied in this paper. A trigonometric series solution of the elastic deflection equation derived by means of Rayleigh\|Ritz energy method was introduced. Compared with the solution presented in references, this solution fulfils the compatibility of deformation and is useful for thin\|walled column. For I\|column and box column, the double edge and center crack models were applied respectively to simulate the tensile flanges that contain mode I though\|wall crack. Particularly, the effects of crack size on maximum elastic deflection of eccentric thin\|walled column under different load and eccentricity states were discussed by use of above solution. The range of crack influence was illustrated according on the load\|crack length curve under the equal Δδ/δ condition, where the parameter Δδ/δ is a ratio of the deflection change caused by crack to the deflection of uncracked column. The analytical and numerical results show that the deflection change caused by crack is increasing with the decrease of slenderness ratio or the increase of eccentricity.

关 键 词：裂纹 弹性挠度 薄壁柱 偏心距 Rayleigh-Ritz变分法 钢结构 

分 类 号：TU391[建筑科学—结构工程]