The Seismic Performance Analysis Of Composite Space Truss-Concrete Frame Hybrid Structure

Composite space truss is a new type of structure in recent years, it is based on traditional’s plate space truss, use the precast slab with ribbed beam to replace the steel members of original structure top chord, thus forming a kind of space grid structure consisting by reinforced concrete beam and slab of upper part and steel truss of bottom part. The structural form can make good use of the materials character that the concrete is in compression and the steel is in tension, and can make the structure’s load-bearing and surrounding functions come into integrit. The hybrid structure which composed by composite space truss and concrete frame structure not only can improve the utilization of building area, but also improved its seismic performance under the condition of in the fully reduced the weight of the structure.Based on the APDL language of ANSYS finite element software, this paper building the different composite space truss---concrete frame hybrid Structure 3D model, study and analysis the response of the hybrid structure under earthquake, discussed the rationality of equivalent stiffness slab simulating composite space truss floor structure, and analysis the seismic performance of hybrid structure by use of different bearing. The main research contents are as follows:Firstly, execute modal analysis of each model to research its dynamic characteristics, and to make preparations for analysis method and damping ratio were selected in subsequent response spectrum analysis and time history analysis.Then, execute response spectrum analysis to study the dynamic response of the Hybrid structure under the horizontal frequent earthquake, contrast each parameters of the models which including deformation features、floor displacement、story drift、frame column internal force and bending moment results to judge its seismic performance; at the same time, Analysis dynamic internal force change of composite space truss member under vertical earthquake action.Secondly, to further discusses the seismic response of different composite space truss---concrete frame hybrid structure with rubber bearings and pin rocker bearing. Through comparing the results of time history analysis and response spectrum analysis, we can find use elastic rubber bearings is advantageous to improve the dynamic characteristics of hybrid structure. And comparing hybrid structure model with pin rocker bearing, rubber bearings is advantageous to improve seismic response of frame structure.Finally, this paper summarizes the findings, and put forward the some currenty existing problems to be solved.