Study On Elastoplastic Seismic Analysis Model Of Intersecting Truss Grid Structure Under Rare Earthquakes

Latticed spatial structure with tubular joints is a new kind of structure usually used in large-span roof, which shows simple and beautiful appearance with few trusses and joints.The research on the structural seismic performance is scarce. The conventional finite element method commonly is employed in engineering design. While it doesn’t consider the influence of panel zone hysteresis behavior, and maybe results in large error and takes more risky for design. So the refinement model considering the hysteretic behavior of joints is needed to analysis the seismic performance. Latticed spatial structural models with three span sizes were analyzed by ANSYS. And the discrete spring model considering the panel zone hysteresis behavior and the conventional finite element method were adopted to study the influences of joint rigidity and hysteretic behavior on global performance of tubular structures, respectively.Mainly for the following several aspects:1.Static analysis of the latticed spatial structure was researched firstly. The internal force and deformation of the main and secondary truss chords and the displacement of joints were calculated and observed. Compared with the conventional finite element method, the result of the discrete spring model showed higher main truss force, lower secondary truss force, and larger joints displacement.2.Dynamic characteristics of the latticed spatial structure were analyzed with two finite element models and the first 30 order self-vibration frequency and mode were displayed.Compared with the conventional finite element model. the discrete spring model showed lower self-vibration frequency, larger period and weaker rigidity, which is helpful to resist earthquakes3.Time history analysis method was presented to evaluate the structural seismic response.It shows that the joint displacement and truss force decreased and the hysteretic behavior of tubular joints has effect on energy dissipation.4.Latticed spatial structural ANSYS models with different span sizes were designed. The effects of different hysteretic behaviors of tubular joints on the truss force and deformation,joint displacement, self-vibration frequency and mode and seismic response were analyzed.The research provides technical support of the seismic design for the latticed spatial structure with tubular joints.