风吸力下跨中设置一根拉条的连续两跨C形檩条的弯扭屈曲  

LATERAL-TORSIONAL BUCKLING OF TWO-SPAN CONTINUOUS C-SECTION PURLINS WITH ONE ANTI-SAG BAR AT MIDDLE SPAN SECTION UNDER WIND SUCTION

作　　者：毛荷月 童根树[1] 

机构地区：[1]浙江大学建筑工程学院,杭州310058

出　　处：《工业建筑》2017年第2期151-157,共7页Industrial Construction

摘　　要：采用开口薄壁杆件理论及考虑腹板局部变形的拉条有效刚度,提出单跨跨中设置拉条的连续两跨C形冷弯薄壁檩条的弯扭屈曲的总势能;经过ANSYS的壳单元分析,从广泛的参数范围考察了檩条的屈曲模态;应用Ritz法得到风吸力作用下连续两跨C形檩条的近似临界荷载计算式,并将其临界弯矩与半跨纯弯简支檩条的临界弯矩进行比较,最终得到临界弯矩系数。Based on the theory of thin-wall members with openings and adopting the efficient stiffness of the anti-sag bars which takes account of the effect of the local deformation of purlin web,the total potential for the lateral-torsional buckling of two-span continuous C-section purlins with one anti-sag bar at middle span section was proposed.The buckling modes were investigated in consideration of a wide range of parameters using the shell element modeling of ANSYS; the approximate formula for the critical loads of the two-span continuous purlins under wind suction was obtained by Ritz method and their critical moments were compared with those of half-span simply supported purlins under constant moment,eventually the critical moment coefficient was got.

关 键 词：连续两跨檩条 拉条 弯扭屈曲模态 临界荷载 临界弯矩系数 

分 类 号：TU392.5[建筑科学—结构工程]