金属阻尼器的耗能能力极大地依赖于耗能构件在轴向、弯曲或剪切荷载下的塑性变形及滞回响应.本文提出一种新型弯剪型防屈曲软钢阻尼器,该阻尼器主要由3个部分组成,两个承受弯曲荷载的X形端板,一块主要承受剪切荷载的软钢腹板,以及两块限制腹板面外变形的外约束加劲钢板.利用ABAQUS有限元软件对比分析了不同形式阻尼器的3个试件,试件区别在于是否存在X形端板和外约束加劲钢板.为了对该新型阻尼器进一步优化,对剪切腹板开缝,改善受力形式和破坏机制,增大腹板塑形变形区域提高耗能效率,利用有限元软件模拟分析了3个不同开缝形式的试件并找出最优开缝形式.分析结果表明该新型软钢阻尼器的滞回曲线饱满,屈服后承载力和耗能能力较其他阻尼器形式都有不同程度的提高,腹板开缝后阻尼器延性明显增大.%The energy dissipation potential of a metallic damper largely depends on the inelastic deformation and the hysteretic response of the energy elements under either axial or flexural or shear loading.In this study,a new type of mild steel damper called a shear-and-flexural buckling-restrained damper is proposed,which consists of three main parts,two end plates of X-configuration allowed to yield under flexural action,a mild steel web mainly subjected to shear loading,and two pieces of restraining steel plate with stiffener clamping the energy dissipation plate to prevent out-of-plane bucking.In this paper the three specimens of different damper are compared and analyzed using ABAQUS,which mainly focus on setting,or not setting,of the buckling plate and end plates of X-configuration.In order to further study the optimization of the new damper,the shear web is slotted to improve force form and failure mechanism,and increase the plastic deformation region to improve energy efficiency of the web,three specimens of different slot forms are analyzed using finite element software to find the optimal slot form.The results show that the new type of mild steel damper has full hysteretic curve,and the post yield bearing capacity and energy dissipation capacity are improved in different degrees compared with other structural forms,and the ductility increases obvious when the web is slotted.
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