Failure analysis of composite pre-tightened teeth joints under bending and tension coupling load

Abstract

With the application of composite pre-tightened tooth joint in engineering practice, relevant studies have found that in actual structures, the joints are subjected not only to axial tension but also to bending and tension coupling force. Therefore, to analyse the load mechanism and progressive failure process of the joint under bending-tension coupling, a experiment loading method for joint structure was first designed in this paper, and axial-tension and bending-tension coupling experiments of single and double teeth were carried out by this method. Then, a three-dimensional model of progressive failure based on the USDFLD subroutine and Tsai-Wu failure criterion is established based on the experiment condition, and finally, the progressive failure process of the joint in the case of bending-tension coupling is analysed by verifying the correctness of the finite element simulation. The study revealed that the top surface of the composite tooth is subjected to the combined effects of tension stress from the bending moment and tension stress from the axial force at the same time, so the joint damage starts at the top surface and the stress state at the top surface of the composite tooth needs to be considered.