梁贯通式钢框架的自复位支撑模块有限元模拟

Finite element modeling of concentrically braced self-centering modular panel of beam-through steel frame

提出了一种适用于梁贯通式支撑钢框架的自复位支撑模块,为结构提供抗侧刚度、自复位刚度和耗能能力,使得结构在震后无残余变形,更换支撑后即可使用。该模块由水平边缘构件(HBE)、竖向边缘构件(VBE)、预应力钢绞线、铰接柱和柔性支撑组成,其自复位刚度由沿HBE布置,锚固在VBE翼缘外侧的预应力钢绞线提供。该模块可在工厂预制,现场用高强螺栓与框架梁连接,便于施工。用有限元软件ABAQUS6.11对该模块进行了精细化建模分析,并详细解释了分析结果。建立7个有限元模型进行参数分析,表明预应力钢绞线的数量、初始预拉力的大小和支撑的横截面积对模块的刚度及耗能能力有较大影响。

A new seismic load-resisting system termed concentrically braced self-centering modular panel( CB-SCMP) is presented,which provides lateral stiffness,self-centering stiffness and energy dissipation for beam-through steel frame.Because of the self-centering ability of CB-SCMP,the structure can re-center after earthquakes and return to service instantly after replacement of the bracings. The CB-SCMP consists of horizontal boundary elements( HBE),vertical boundary elements( VBE),post-tensioned strands,leaning columns and tension-only steel bracings,whose self-centering stiffness is provided by the post-tensioned strands which are parallel to HBE and anchored to the outer flange of VBE. The CB-SCMP can be shop prefabricated and then transported to the construction site for rapid installation into the main frame through bolt connections to the frame girder. A refined finite element model was established in ABAQUS6. 11 and the results were interpreted in detail. The effects of the numbers of post-tensioned strands,the initial pretention and the crosssectional area of the bracings on the stiffness and energy dissipation capacity of the CB-SCMP were investigated through 7finite element models.