Design Of A New Bearing On The Large Net Shell Roof Tank

The structure of the plate rib roof can't meet the need of the constantly enlarging storage tanks, thus more steel/aluminum net shell roofs have been used on the large storage tanks. The bearing between the roof and the tank wall is a key component, because it directly affects the strength and stability of the net shell roof. In this paper, a new type of net shell roof bearing structure is proposed in order to relieve the stress on the bearing and the net shell roof. The proposed structure has several features compared with the existing bearings: the net shell roof with the new bearing can allow a certain amount of radial displacement, and the bearing can also rotate within a certain angle. According to the actual loading status, strength and stability analysis of the overall net shell roof and the bearing's partial structure are carried out respectively. The overall model of the net shell roof is established by ANSYS, and different boundary conditions are defined on the roof under two working conditions of "full-span live load" and "half-span live load". Then the overall static strength calculation and stability analysis of the roof are completed. Based on the results of the overall analysis, the strength of the bearing's partial model is analyzed in ANSYS Workbench. Research shows that when the net shell roof is under load, the roof is allowed to make radial displacement and the bearing to make angular displacement. Thus the burden on the bearing and the net shell roof is relieved, and the strength and stability of the overall roof meet the requirements. Moreover, many regions of the bearing can share the horizontal force, which helps to reduce the load on the bolts and improve the safety of the bearing structure. And the strength of the bearing meets the requirements.