Research on Shell Element Modelling of Single-layer Cylindrical Reticulated Shell with Welded Hollow Spherical Joints

In general, the reticulated shells share long span and large numbers of elements, which results difficult to test the full size dynamic performance under strong ground motion excitations on shaking table. Therefore, the computer simulation is necessary in the research of these structures. In order to less computer time, a simplified model regardless of joint stiffness is commonly used in the analysis. However, in realized structures some hollow spherical joints would be yielded or even deformed during the strong earthquake, these yielded joints would have a certain effect on the response of the whole structure. To evaluate the effect of these joints, a shell element model considered the joint stiffness is built, and the real dimension joint is utilized to achieve the result similar to the real structure as much as possible.

The key of modelling is to create the hollow spherical joint which could not only cooperate with the circular steel tubes on it but also simulate the real joint load-carrying capacity well. A beam element model with size same to the former model is built to research on the difference of their seismic performance, the difference between these two models is just of their joint stiffness. The top-point displacement responses are recorded in the analysis. It is shown that the difference of the response is obvious, so the joint stiffness effect is not small enough to be neglected.