Key Techonology Research On The Reticulated Dome Of Storage Tanks With A New Bearing Structure

With the maximization of refined oil storage tanks, various forms of single-layer spherical reticulated domes are widely used as the tank roof structure. However, the domestic research on the reticulated domes of storage tanks is not enough systematic and thorough. Based on the existing research results of our research group, the full-scale model experimental study of the new bearing structure applicable for a 50000 m3 storage tank with reticulated dome is firstly conducted, and its safety and reliability under the design condition is verified. Then, the static analysis and overall stability analysis on the storage tanks with a reticulated dome, which adopt the new bearing structure, are carried out, and the effects of different factors on the strength, stiffness and overall stability of reticulated domes are investigated. Finally, a new reticulated dome structure with variable section for large storage tanks is proposed from the perspective of lightweight. The main works are as follows.(1) After sizing optimization and analysis of the new type bearing structure developed by our research group, the full-scale model of this structure applicable for a 50000 m3 storage tank with reticulated dome is designed and manufactured to conduct the experimental study. The measured values and finite element analysis results of the Tresca equivalent stress intensity of the measuring points on the specimen are analyzed and compared, the experimental results and numerical simulation results both show that the new bearing structure performs well and satisfies the design requirements.(2) Taking the influence of collaborative working between upper dome and lower tank body into account, the static analysis and calculation on the reticulated domes of storage tanks which adopt the new bearing structure are carried out. The influence of dome parameters, such as the ratio between vector height and span, the segmentation frequency of reticulated shells on the mechanical properties of tank body, and the influence of tank body parameters including the ring beam size, the thickness of top tank wall on the mechanical properties of reticulated dome, are both investigated. Meanwhile, a simplified method to calculate the strength and stiffness of reticulated domes of storage tanks is presented, and the correctness of the method is verified in reticulated dome storage tanks with different volumes.(3) Considering the effect of installation deviation, the overall stability analysis on the reticulated domes of storage tanks which adopt the new bearing structure is carried out. The overall stability analysis model is established by taking the dual nonlinear, lower tank body and joint installation deviations into account. The influence of different values of installation deviation on the tank reticulated domes with different volumes is studied, and the control value of installation deviation is presented.(4) A new reticulated dome structure with variable section for large storage tanks is proposed, it can improve the material utilization of members and reduce the weight of reticulated dome. Then, taking the 50000 m3 storage tank as an example, corresponding analysis and calculation of the proposed structure are conducted, the results indicate that this new structure is feasible. Finally, its applicability in storage tanks with different volumes are discussed.