Study On Vertical Progressive Collapse Resistance Of Frame Structure With Dampers

During the process of vertical progressive collapse of the structure,the geometric configuration of the structure is changed due to the sudden failure of the component,and it will cause the vibration of the component.In addition to the dynamic effect,the vertical progressive collapse of the structure is accompanied by the large deformation of the structure.In this process,the structure is constantly searching for a new path to maintain the stability and equilibrium state.Therefore,it is of great significance to reduce the structural dynamic effect and vertical displacement.Damping is the fundamental reason of the structural vibration attenuation.Increasing the damping is an effective measure to reduce the structural dynamic effect and the structural deformation.This paper based on characteristics of vertical progressive collapse resistance of structure,analyzes the influence of damper on vertical progressive collapse dynamic effect and vertical displacement of concrete frame and steel frame structure by SAP2000,and reveals the performance of vertical progressive collapse resistance of frame structure with dampers,then proposes relevant design proposals.Specific research work is as follows:(1)Study on the influence of damping on vertical progressive collapse dynamic effect and vertical displacement.Taking the column-beam combination(single degree of freedom model)with viscous dampers as the research object,assuming that the combination collapsed under vertical load due to column sudden failure,changing the parameters such as damping ratio,natural periods and yield strength of the beam end,study the parametric influence of vertical progressive collapse dynamic effect and vertical displacement by the nonlinear dynamic analysis method.(2)Theoretical analysis on the performance for vertical progressive collapse resistance of RC frame structures with dampers.Taking the multi span and multi story concrete frame as the research object,changing the types,parameters,number and positions of the damper,study the vertical progressive collapse resistance performance by using dismantled component method for nonlinear dynamic analysis of the damper structure based on failure condition of bottom intermediate column at the longer side.Discuss the influence of the types,parameters,number and positions of the damper on vertical displacement,the plastic hinge angle and its distribution.And compared with the ordinary concrete frame structure without damper.(3)Theoretical analysis on the performance for vertical progressive collapse resistance of steel frame structures with dampers.Taking the multi span and multi story steel frame as the research object,changing the types,parameters,number and positions of the damper,study the vertical progressive collapse resistance performance by using dismantled component method for nonlinear dynamic analysis of the damper structure based on failure condition of bottom intermediate column at the longer side.Discuss the influence of the types,parameters,number and positions of the damper on vertical displacement,the plastic hinge angle and its distribution.Compared with the ordinary steel frame structure without dampers and also a preliminary longitudinal contrast with concrete frame structure in the same situation.(4)Study on the design theory of vertical progressive collapse of frame structure with dampers.Based on the above theoretical research,the requirements of vertical progressive collapse resistance of the frame structure and its characteristics,study the design theory of the vertical progressive collapse resistance of frame structure.And Put forward some relevant design proposals.