Study on failure of single-bolt double-lap composite joints based on test and numerical emulation

In order to study the mechanical properties of ZT7G/LT-03A carbon fiber reinforced composite bolted joints, the single-bolt double-lap joints tests were carried out with 3 kinds of ply and 3 kinds of width, and the effects of the different ply ratios, width to diameter ratios on the failure load and failure mode were analyzed. Then, the failure process of the specimens was simulated by using the progressive damage and failure analysis method. The failure mode and failure load of the model are consistent with that of the specimen, which verified the accuracy of the model. On this basis, the stress and damage status of each ply during initial load shedding were studied, and the influence of the ply ratios and width to diameter ratios on the performance of laminates was further studied. The results show that when the width to diameter ratio of laminates increases, the failure mode changes from tensile failure to bearing failure, and to change the ply ratios does not affect the failure mode in a certain range.