偏心支撑钢框架结构是在中心支撑钢框架的基础上改进形成的。偏心支撑钢框架结构在罕遇地震作用下，耗能梁段率先屈服，通过其塑性屈曲变形耗散大量地震能量，是高层钢结构中较为理想的抗侧力体系。随着我国经济和钢结构产业的不断发展，高层偏心支撑钢框架结构的应用也越来越多。为对工程实践提供理论指导，本文对K型偏心支撑钢框架结构的弹塑性受力性能进行研究。 本文利用Sap2000软件对K型偏心支撑钢框架采用实体建模的方法进行有限元数值模拟分析。考虑了耗能梁段长度、耗能梁段腹板高厚比、支撑杆件长细比、支撑杆件布置形式及结构高跨比的影响，建立了27个偏心支撑钢框架的整体模型，运用Pushover分析方法深入研究了性能点的确定、楼层位移、层间位移以及塑性铰的发展状况等，研究结果表明：在地震作用下，偏心支撑钢框架通过耗能梁段的塑性屈曲变形耗散大量地震能量，使得其它结构构件处于弹性阶段，具有很好的延性和抗震性能，建议实际工程中优先考虑采用偏心支撑钢框架结构；耗能梁段过长时，结构的整体抗侧刚度小，地震位移反应大，耗能梁段过短时，结构的整体抗侧刚度大，地震作用下吸收地震能量多，建议耗能梁段的长度值取1.1 ～l.3 ；罕遇地震作用下主要依靠耗能梁段腹板的剪切屈服进行耗能，建议耗能梁段腹板的高厚比值取为35～55；支撑的长细比较大时，容易发生屈曲而降低结构的耗能性能，支撑的长细比较小时，结构整体侧向刚度大，承受的地震力大，延性和耗能能力较差，建议支撑杆件长细比取为30～37；耗能支撑采用合理的错列布置，可提高结构的整体抗侧刚度，改善结构的抗震性能，建议支撑布置形式采用合理的错列布置形式；结构的高跨比较小时，结构整体侧向刚度大，延性和耗能能力差，高跨比较大时，结构的延性较好但承载能力较低，建议结构高跨比取值为0.5～0.8。

Eccentrically braced steel frame structure based on concentrically braced frames.Under the rare earthquake action，dissipative link of an eccentrically braced frame becomes plastic earlier.Then it consumes the energy of earthquake by its plastic buckling deformation. It is a ideal high-rise steel structure of resistance to lateral force system.With the continuous development of economy and the steel structure industry in China,the application of high-rise eccentrically braced steel frame structure is also more and more.In order to provide theoretical guidance for engineering practic,the elastic-plastic stress performance of the K shape eccentrically braced steel frame structure were studied in this paper. For the K shape eccentrically braced steel frame the finite element numerical simulation analysis is finished by finite element software sap2000.Considering the different length of link beam,different height-to-thickness ratio of web,different slenderness ratio,different layouts of brace and differen pitch of Structure and establishing 27 overall models, performance point determination,the floor displacement, the interlayer displacement,and the development of the plastic hinge were studied.Research results show that.Under the action of the earthquake,the dissipation beam section of eccentrically braced steel frame buckling and reduce much seismic energy.It has the very good ductility and seismic performance. Suggested that the eccentrically braced steel frame should be used firstly in the practical engineering.When the dissipative link is too long,the whole lateral stiffness of the structure is small and earthquake displacement reaction is large.When the dissipative link is too short,the whole lateral stiffness of the structure is big and it absorb more seismic energy.Suggested that the length of the energy dissipation beam section is between 1.1 and 1.3 .It mainly rely on the web shear yield of the energy dissipation beam section for energy consumption.Suggested that the web thickness ratio of the energy dissipation beam is between 35 and 55.When the support slenderness ratio is large,it buckling easily and reduce the energy dissipation performance of structure.When the Support slenderness ratio is small,The integral lateral stiffness and earthquake force is big.Suggested that the support slenderness ratio is between 30 and 37.The reasonable staggered arrangement of the energy dissipation beam support can improve the whole lateral stiffness of the structure and the seismic performance. Suggested that the Support arrangement adopt reasonable staggered arrangement form.When the depth-span ratio of Structure is small,the whole lateral stiffness of the structure is large and the energy dissipation is poor.When the depth-span ratio of Structure is large,the ductility of structure is good and the bearing capacity is small.Suggested that the depth-span ratio of Structure is between 0.5 and 0.8.