The Elasto-Plastic Dynamic Response Research On Spatial Steel Tube Arch Truss Subjected To Earthquake

The spatial steel tube arch truss is mostly applied to the roof of gymnasium, exhibition center and so on because of its excellence in aspect of figure, mechanics and construction. Earthquake happened very common in our country which is the natural disaster severely damaging people's lives and properties. Nowadays anti-seismic performance of arch truss under earthquake is not yet fully understood although. So it is very important for theory and praxis to make research on the dynamic response of arch truss subjected to earthquake.The elasto-plastic dynamic response for arch trusses have been studied under earthquake action using the ANSYS program, In the course of analysis, non-linear analysis of material and geometry and the effect of gravity and damp were included, the detail work is as followed:1. The time-history analysis of dynamic response on arch truss under anti-seismic performanceThe finite element modal of arch truss was set up on the basis of fitting the first stage anti-seismic design. The dynamic response was studied with the increase of earthquake according to the characteristic targets-acceleration curves , from which non-linear dynamic history analysis due to 2-dimention earthquake was calculated under Ninghe seismic wave, the detail response targets are as followed: (1) the response of node displacement, (2) the response of element stress, (3) the response of axial force, (4) the response of element plastic strain, (5) the response of element kinetic energy. The study results revealed that: the dynamic response of structure increased with the increasing of the seismic acceleration amplitude. There must be a certain plastic development process before the failure appears under severe earthquake action, and the failure of structure is caused due to the severe yield elements getting together and the structure rigid reducing, the instability collapse took place with losing the capability subjected to earthquake and keeping the initial shape.2. The parametric analysis of arch truss dynamic response under earthquake actionIn the course of parametric analysis, The response under different kinds of seismic waves, roof mass, imperfection and rise-span ration were studied. The study results revealed that: dynamic response results of structure may be different obviously under different kinds of seismic waves or different earthquake direction, dynamic instability collapse of arch truss subjected to severe earthquake is not the only form of dynamic failure, strength failure may also occur. With the roof mass increasing the dynamic response results became obvious. The initial imperfection debases the critical load. The critical load increased with the height increased and the failure mode of the structure changed from instability collapse to strength failure.