Geometrical effects on the LJF of tubular T/Y-joints with doubler plate in offshore wind turbines.

In this study, the Local Joint Flexibility (LJF) of tubular T/Y-joints with doubler plate under in-plane bending (IPB) load is investigated. In the first step, a finite element (FE) model was developed and verified using the available experimental results. In the next step, 252 FE models were generated to investigate the effect of the joint geometry on the LJF factor (f_LJF). Results showed that the increase of the doubler plate size results in the considerable decrease of the f_LJF. Also, the f_LJF of a T/Y-joint reinforced with doubler plate can be down to 26% of the f_LJF of the corresponding unreinforced joint. Despite the considerable effect of the doubler plate on the f_LJF, there is not any study on the f_LJF of the tubular joints with doubler plate. Hence, after a parametric study, FE results were used to propose a parametric formula for determining the f_LJF. [ABSTRACT FROM AUTHOR]