The Research On The Diagonal Web Member Truss Strengthened Story In Framework-core Tube Structure

In recent years, along with the speedy progress of technological advancement and social advance the low-rise buildings have become increasingly cannot meet the needs of people’s life and production. Higher and higher building structures come into being, these higher and higher building structures not only greatly improve usage of space, also propose more stricted requisitions of the structure performance. Framework-core tube with strengthened stories can greatly enhance the ability of resisting horizontal load of the structure and can make the structure has a twofold resistance to lateral force system. But the strengthening layers’ installation can also lead to buildings’ uneven stiffness distribution along height so a s to lead to mutation of internal force and displacement of strengthen layers and layers near the strengthen layers. Structures with uneven distribution of the internal force under seismic action are difficult to form the yield mechanism and easy to form weak link, which leads to structural damage and even overturn.At present,Framework-core tube with strengthened stories mostly use beam strengthening layers, but there are few perfect theoretical research and engineering experience of strengthened stories’ study which have herringboned braces in framework-core tube structure.So, this paper aims at strengthened stories’ study which have herringboned braces to do the following research: 1. The article uses the computer program of analysis of limited element Midas/Gen and design computer program PKPM to do the analysis of12strengthened layer of diagonal web member truss framework-core tubes models with different location, quantity, strengthening layer stiffness’natural period of vibration,seismic force,floor displacement and internal force in the elastic stage; sums up the determination methods of the optimal positions and quantity of the strengthening floors considering the maximum structural displacement and displacement between strengthen layers and the influence to the internal force of the floors and the influence of the internal forces of the floors,frame corner columns,side column and the internal force of shear walls.2. Using Midas/Gen and EPDA&PUSH softwares on four models of different locations of strengthen layers to do the static elastoplastic analysis. Sum up the producing orderliness of plastic hinges, compare and analyze the ability of the four models’capacity curves,the relationship of the inter-layers’shear force,the relationship of the inter layer displacement angles, the ductility ratio of bottom corner pillar and structure the characteristics of performance points and the distribution laws of shear between outer framework and inter tube.3. Using Midas/Gen and EPDA&PUSH softwares on four models of different locations of strengthened stories to do the analysis in the elastic stage under upside-down triangular load and the action of earthquake, so as to obtain the results:the influence to the structural displacement by the outrigger’bending stiffness ratio,the outrigger’shear stiffness ratio,the frame column’bending stiffness ratio and the core tube’bending stiffness and the influence to side column’axial force by the outrigger’bending stiffness ratio.