Cooperative Study on Strength and Deformation Capacity of Steel Beam-Columns

本文的主要研究目的是：(1)通过文献调查收集以往钢梁柱强度和变形能力的试验数据，并找出影响因素；(2)阐明新开发的低屈服比高强钢梁柱与传统低碳钢梁柱的性能对比；(3)建立通用型的梁柱强度和变形能力评定公式。本研究项目的实验和理论研究项目如下：(a)建立钢梁柱强度和变形能力数据库，并对计算公式的准确性进行研究；(b) h形梁柱在恒定轴力和反复反对称弯矩作用下的面内弹塑性失稳研究；(c) l形梁柱局部屈曲或侧向扭转屈曲弹塑性失稳研究。(d)在恒定轴力和交替重复双曲率弯矩作用下冷弯方管梁柱局部屈曲行为研究；(e)在恒定轴力和交替重复水平力作用下，加或不加填充混凝土的方管悬臂梁柱弹塑性行为研究；(f)对有或没有填充混凝土的中央受压方管柱的屈曲强度进行了研究；(g)对冷成形和特殊热处理的圆管的强度和变形能力进行了研究，该研究基于张联试验、短柱压缩试验和反复弯曲试验。试件采用SS400、STKR400等低碳钢或新开发的低屈服比高强度钢，其强度与SM570相当，屈服比约为0.8。研究了材料性能差异对梁柱性能的影响，以及轴力比、宽厚比、长细比、加载条件和填充混凝土的存在等关键参数的影响。每项调查的详情载于表格1的报告内。以及在国内和国际会议和期刊上发表的技术论文。少

Main purposes of the research presented are: (i) to collect previous experimental data of strength and deformation capacity of steel beam-columns by the literature survey, and to identify influential factors, (ii) to clarify the behavior of beam-columns made of newly developed high-strength steel with low yield ratio, comparing with those of conventional mild steel, and (iii) to develop general type of evaluation formulas for strength and deformation capacity of beam-columns. Items investigated experimentally and theoretically in this research project are as follows: (a) Development of a data base of strength and deformation capacity of steel beam-columns and investigation of the accuracy of evaluation formulas, (b) Investigation of elasto-plastic in-plane instability of H-shaped beam-columns subjected to a constant axial force and repeated anti-symmetrical bending moment, (c) Investigation of elasto-plastic instability due to local buckling or lateral torsional buckling of L-shaped fr … More ames composed of H-shaped column and elastic beam, subjected to a constant axial force and a monotonic horizontal force, (d) Investigation of local buckling behavior of cold-formed square-tubular beam-columns subjected to a constant axial force and alternately repeated double curvature bending moment, (e) Investigation of elasto plastic behavior of square-tubular cantilever beam-columns with or without filled-concrete, subjected to a constant axial force and alternately repeated horizontal force, (f) Investigation of buckling strength of centrally loaded square tubular columns with or without filled-concrete, (g) Investigation of strength and deformation capacity of cold- formed and specially heat-treated circular tubes based on tensile coupon tests, stub column compression tests and repeated bending tests. Test specimens were made of either mild steel such as SS400 and STKR400 or newly developed high strength steel with low yield ratio, of which strength was equivalent to SM570 and yield ratio was about 0.8. The effects of the difference in material properties on the beam-column behaviors were investigated together with the effects of other essential parameters, such as axial force ratio, width-thickness ratio, slenderness ratio, loading condition and existence of filled-concrete. Details of each investigation were given in the report of Form 1. as well as in the technical papers published in national and international proceedings and journals. Less