T形截面压杆的腹板局部屈曲

《结构设计规范》（ＧＢＪ１７－８８）对Ｔ形截面压杆腹板高厚比的限值规定得过严，影响剖分Ｔ型钢的推广应用。分析表明：Ｔ形截面压杆板件相关屈曲的临界应力等同于杆件绕剪心轴扭转屈曲的临界应力。当杆件满足弯扭屈曲验算要求后，一般无须再对局部稳定进行验算．但是，高厚比很大的硬板也有可能单独屈曲，因而仍然需要对腹板高厚比加以限制。为此提出了相应的建议。此外，还对Ｔ形截面压弯构件的腹板稳定进行了分析。

THE STEM LOCAL BUCKLING OF T-SECTION COMPRESSION MEMBERS

The limiting slenderness of T-section stems prescribed in the Code for Design of Steel Structures (GBJ17-88) is too restrictive so as to hinder the promotion of using the hot-rolled cut T-section. It is shown that the critical stress of the interactive buckling of the plate elements is the same as that of the member in torsional buckling about the shear center axis. When a T-section member satisfies the verification on flexural -torsional buckling, there is generally no need to perform a buckling check for plate elements. However a too slender stem may buckle by itself instead of interactive buckling so that a limiting width-thickness ratio is sun necessary. Suggestion is made for revising the relevant clause of the Design Code. The stability of T- section beam-column stems is also investigated.