- 摘 要
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鄭廷銀
（南京建筑工程學院 210009）[提要] 采用有限元法完成了折線形過渡支座、圓弧形過渡支座及直角形突變支座鋼吊車梁在同一條件下的應力、變形分析；通過各受試梁的各應力場分析，找出了各支座應力分布規(guī)律的差異和疲勞裂紋敏感區(qū)；由各應力集中系數(shù)分布圖，捕捉到了疲勞裂紋首發(fā)點；運用本文所建立的“疲勞裂紋擴展驅(qū)動能”等新概念，分析了各型支座的疲勞性能；最后結(jié)合制作加工的難易程度和經(jīng)濟分析等，提出了上述三類變截面支座的適用條件。
[關(guān)鍵詞] 鋼吊車梁 變截面支座 疲勞性能 應力集中帶寬 裂紋擴展驅(qū)動能This paper successfully obtains the stresses and strains for the abutment of steel crane beam by using the finite element method, in which the abutments are the transition of polygonal lines and right angle. Then the difference of the stress distribution rules and the sensitive regions of fatigue crack have been found by analysing the stress field in the beams tested. And the first happening point of fatigue crack is caught from the distribution chants of stress concentration factor. The fatigue property of the three kinds of abutments is studied by the new theory of "driving energy for fatigue crack expanding" proposed in this paper. At last, the applying conditions of the abutments are suggested according to the difficult degree of manufacturing and the economy analysis.
Keywords: steel crane beam; variable section abutment; fatigue property; stress concentration, driv-
ing energy; fatigue crack expanding
