非加劲钢板剪力墙的高阶弹性剪切屈曲分析

非加劲钢板剪力墙(SPSW)结构在水平荷载作用下易屈曲,形成主拉压应力场,并以拉力带方式提供水平承载力及抗侧刚度。传统拉杆模型(SM模型)用于非加劲SPSW结构分析或设计时忽略压力场的贡献,一般会低估高厚比较小的非加劲SPSW结构的抗侧能力。非加劲SPSW结构在水平力作用下会形成多波面外变形,与剪力墙板的高阶屈曲相似,可通过在修正的SM模型中引入对应于高阶屈曲的主压应力来反映压力场贡献,提高模型分析精度。考虑剪力墙板高厚比、高宽比及边缘构件刚度的影响,共设计66个单层、单跨和梁柱铰接的非加劲SPSW算例,并进行弹性屈曲分析。分析结果表明,高厚比及边缘构件刚度对非加劲SPSW结构的剪切屈曲系数影响不大;随着剪力墙板高宽比的增加,非加劲SPSW结构的剪切屈曲系数呈增大趋势。采用Matlab程序对66个非加劲SPSW算例的2～5阶剪切屈曲系数结果进行统计分析,并提出了简化公式。

High-order elastic shear buckling analysis of unstiffened steel plate shear wall

The unstiffened steel shear wall(SPSW)structure was prone to buckling and development of the principle tension and compression field.The lateral strength and lateral stiffness of unstiffened SPSW were provided by inclined tension field.The traditional strip model was presented to simulate the seismic behavior of an unstiffened SPSW structure and the contribution of compression field was ignored.However,for unstiffened SPSWs with small or moderate height-to-thickness ratio the lateral bearing capacity was underestimated.Especially,the multi-wave out-of-plane deformation of unstiffened SPSW subjected to cyclic loading was similar to the high-order buckling mode.Therefore,to improve the accuracy of the simplified analytical macro model,the high-order buckling load could be introduced to consider the effect of compression field of an unstiffened SPSW structure.In this paper,a total of 66 single-story,single-span unstiffened SPSW structures with pinned connections were designed,considering the effect of height-to-thickness ratio,height-to-span ratio,as well as frame-to-wall stiffness ratio and the buckling analysis was performed.The analytical results show that the height-to-thickness ratio and frame-to-wall stiffness ratio have less influence on the shear buckling coefficient of an unstiffened SPSW structure.With the increase of height-to-span ratio the shear buckling coefficient shows an increasing tendency.The MATLAB program was adopted for regression analysis on the high-order shear buckling coefficients of unstiffened SPSW structures,and the calculating formulas were proposed.