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    饒芝英  童根樹(shù)    （浙江大學(xué)土木系  杭州 310027）

[提要]  提出了與鋼結(jié)構(gòu)穩(wěn)定性計(jì)算有關(guān)的多高層鋼結(jié)構(gòu)的分類，由此可以更好地理解鋼結(jié)構(gòu)穩(wěn)定性的計(jì)算方法，合理選擇鋼結(jié)構(gòu)穩(wěn)定計(jì)算的圖表或公式，判斷某些鋼結(jié)構(gòu)規(guī)范穩(wěn)定性計(jì)算條文的合理性。
[關(guān)鍵詞]  鋼結(jié)構(gòu)  穩(wěn)定性  框架  支撐  高層建筑

A classification of multistory and tall steel structures is presented in seismic design, which is closely related to the stability design. Based on this classification, the designer may make a correct decision on what kind of method should be used in the structural analysis( first order or second order analysis) and select an appropriate formula or table from the code to determine the column effective length or calculate the column load-carrying capacity. This paper summarized the definitions of total 7 technical terms, i. e. sway and non-sway frames, laterally stiff structure and laterally flexible structure, and strongly braced, weakly braced and unbraced frames. The presented classifying method is based on a research on the buckling of unbraced,weakly braced ancl fully braced frames. Criteria for judging whether a structure is fully braced or not is presented. The stability design formula for weakly braced frames is put forward.
Keywords:  steel structure; stability; frame; brace; tall building