Load distribution of composite pre-tightened teeth connections embedded with soft layers

Due to the brittleness of composite materials, the load distribution of each tooth in the force transmission process of the composite pre-tightened tooth joint is uneven, so that the strength of the composite material cannot not be brought into full play. Based on the mechanism of force transfer in natural biological structures, the mechanism of soft layers with different stiffness in the composite pre-tightened tooth joints affecting the load distribution ratio of each tooth was studied. First, experiments were performed to investigate the influence law of soft layers with different thickness and elastic moduli on the bearing capacity, damage mode, and load distribution ratio of the specimens. Then, a progressive damage model of the joint was established and modified according to experimental results. Finally, the mechanism of soft layers adjusting the load distribution ratio of the composite pre-tightened tooth joints was investigated by the finite-element model. The following conclusions were drawn: (1) the application of soft layers can achieve a uniform load distribution among the teeth in the multi-tooth joint and improve the bearing capacity of the composite pre-tightened multi-tooth joint; (2) the elastic modulus and thickness of the soft layers significantly affected the load distribution ratio of the joint. When the elastic modulus of the soft layer varies, the thickness of soft layers required for reaching the optimal load distribution ratio for each tooth of the multi-tooth joint changes.

Automated summary

This study investigates the mechanism of how soft layers affect the load distribution in composite pre-tightened tooth joints using experiments and numerical simulations, and draws relevant conclusions.