钢板组合剪力墙轴心受拉性能研究

Research on Axial-Tension Performance of Steel Plate Composite Shear Walls

当结构的高宽比较大时,在设防与罕遇地震作用下高烈度区的超高层结构的核心筒剪力墙可能承受倾覆力矩引起的巨大拉力,垂直于地震作用方向的核心筒翼墙受力状态接近于轴心受拉。由于混凝土抗拉强度较小,常采用钢板组合剪力墙来抵抗较大的墙肢拉力。采用非线性有限元法,对钢板组合剪力墙在轴心受拉作用下的开裂荷载、刚度变化、滞回性能与受拉承载力进行了较为全面的研究,表明混凝土对构件的轴拉承载力与刚度具有一定贡献。给出了钢板组合剪力墙在轴心受拉状态下最大裂缝宽度的计算方法,分析了墙体含钢率以及型钢、钢筋布置方式对裂缝宽度的影响。钢板组合剪力墙轴心受拉缩尺模型试验结果表明,有限元数值分析与模型试验吻合良好。在此基础上,提出了钢板组合剪力墙受拉状态下的设计建议。

When a super high-rise building is subjected to high intensity earthquake and the building has large height-width ratio,the overturning moment under rare earthquake may cause large tensile stress in the core tube shear walls.Core tube wing walls perpendicular to the direction of earthquake are subjected to axial tension.Since the tensile strength of concrete is small,steel plate composite shear walls（SPCW）are adopted to resist large tensile stress.By using nonlinear finite element method,the stress of SPCW under axial tension is studied,including cracking load,stiffness variation,hysteretic performance and tensile strength capacity.The results show that concrete contributes to the tensile strength capacity and axial stiffness of the component.A method for calculating the maximum crack width is proposed.The factors influencing the crack width are evaluated,including steel ratio,layout of steel section and rebar.A reduce-scaled axial tension SPCW test is carried out and it has a good agreement with the finite element analysis result.Based on experimental and analytical study results,the recommendations for designing SPCW under axial tension states are proposed.