Failure analysis of composite F-joint structures under tensile loading: Experimental and numerical study

•The failure mode and strain distribution of the new F-joint were studied.•The material selection and production experience of the F-joint were introduced.•The differences in the damage process, failure modes and strain distribution between two different connection types of F-joint were analysed.•The finite element models were able to predict the mechanical response and damage in F-joints accurately. This paper presents an investigation on the failure process of two different types of composite frame joints (F-joints), one is connected by high-lock bolts (FH) and the other reinforced by high-lock bolts and adhesive (FHA). The mechanical behavior of F-joints subjected to out-of-plane tension load is analyzed by experiment and numerical simulation. Test results show significant differences in the damage process, failure modes and strain distribution between FH and FHA. The strength of FHA increases nearly 13% compared to FH. Three-dimensional finite element models considering failure criterion and damage evolution are developed and implemented in the commercial code Abaqus/Standard through a user-defined subroutine UMAT. Cohesive zone model is used to simulate the adhesive layer damage of FHA. Simulating failure load and the damage process match the experimental data. The information on the failure mechanism and final failure load of composite F-joints is useful for the optimal design of such joints.