Multi-dimensional Earthquake Response Of Large-span Prestressed Lattice Shell Structure

The prestressed lattice shell structure is a kind of novel space structures, which has an extensive application in large-span industrial and civil buildings in recent ten more years. Because its fitness of stress distribution, large stiffness, light weight, easily making and installing, its security is recognized excessively. Multi-dimensional earthquake response of large-span prestressed lattice shell structure was studied by time history analysis.First, based on seismic traveling wave theory, the response of the Panzhihua Gymnasium prestressed lattice shell structure under different seismic wave velocities is analyzed by the large-scale finite element program ANSYS. Second, a new large-span prestressed lattice shell model is built, on which static and dynamic analysis of lattice shell under different arrangements of cable and different value of prestressed is performed. Finally, elasto analysis of lattice shell mentioned above under different seismic wave velocities is performed, which compares with the result of elastic analysis.The study indicates that under the action of the seismic, the coefficient of seismic internal force of central and marginal member bars is not great, and seismic effect is not conspicuous. But the coefficient on the bars that 1/3 far from the supports is obviously great,and the seismic effect on it is clear. The influence of seismic traveling wave on marginal member bars is not great, but obviously great on central bars. Moreover the smaller is the wave velocity, the greater is the internal force of central bars, and the more conspicuous is the effect of traveling wave, which should be considered in the design. Under the action of rare seismic, the influence on structural performance of material plasticity development is great, internal force distributes again when the structure enters plasticity. The internal force of yielded bars tend to dwindle, while the one of unyielded bars tend to increase, as the result, the strength of structure becomes more uniform. The arrangements of cable and value of prestressed is important for static and dynamic performance of prestressed lattice shell structure, the prestressd force cables suit to dispose on the margin of the shell.