Study on synergistic mechanism of tube–gusset plate connections with multi-stiffened plates

Abstract

In this study, an experimental investigation and theoretical analysis of the synergistic mechanism of multi-stiffened ring plates under loading were performed. The experimental programme included material tests and nine groups of static loading tests on X-type tube–gusset plate joints with two stiffeners. This was followed by a numerical simulation study in which the numerical models were first developed and validated against the experimental data. The validated models were then utilised to perform numerical investigations of typical joints containing three, four, and five ring plates to generate additional results over a broader number of stiffened ring plates. From the experimental and numerical results, the load distribution of each stiffened ring plate was extracted under the load component perpendicular to the chord axis, and the results were compared with the calculation results of the Japanese code to verify the applicability of the calculation method in the code. This comparison revealed that there were significant differences between the standard calculation results and the numerical analysis results. Thus, based on the characteristics of the load transfer and deformation of joints with multi-stiffened ring plates, a rigid beam–spring bearing calculation model was proposed, and the corresponding calculation program was implemented. The results of the program calculation were compared with the numerical analysis results, and the improved rigid beam–spring bearing model could accurately calculate the distributed load of each stiffened ring plate. Thus, the proposed program can be used to guide the design of joints in actual engineering projects.