THE USE OF DIRECT ANALYSIS METHOD FOR YUJIAPU TRAFFIC HUBS
Goman Ho 1*
1 Arup Fellow, Hong Kong, China
The roof is 145m long, 80m wide and 26m tall. It is a single layer diagrid shell roof from a concept of natural sea shell. The roof was designed for wind, seismic, snow load and also checked for progressive collapse. Wind tunnel tests were carried out for wind load and also for snow drift with consideration of wind direction and sunlight. Seismic Intensity of 7 (PGA=0.15g for 475 years return period) were considered for the steel roof itself and also the effect due to the movement of underground structures were also study. Generally speaking, 2nd order geometric nonlinear analysis should be considered in roof design process. However, it is not be easy to include the initial imperfection of members in the global analysis. For this project, the initial imperfection of both the structures and members (i.e. P-D-d / P-∆-d) are all considered through the most advanced direct analysis tools. The global collapse load for the roof was determined to ensure that the roof won't collapse at its ultimate limit state.This paper presents the concept of the roof structural arrangement, use of form finding to determine the optimum geometry, the use of direct analysis to assist the design.
Single layer dome; direct analysis; form finding; stability analysis; initial imperfection; traffic hubs; plastic hinges, second order analysis; critical load, buckling.