A prediction method of the failure load and failure mode for composite pre-tightened tooth connections based on the characteristic lengths

In the conventional methods, the failure load and failure mode of composite pre-tightened tooth connections are determined by experiment. To determine the failure load and failure mode of the composite pre-tightened tooth connection without performing experiments, a new method based on the characteristic lengths is presented in this paper. This method involves three steps: first, based on the concept of the method to determine the shear characteristic length, the compressive characteristic length is defined and the characteristic length of composite tooth can be determined; second, the stress distribution of the composite joint is analyzed by the use of a finite element method; finally, combined with failure criterion and the stress distribution of the composite joint, the failure load and failure mode of this joint can be determined by the compression factor fc and shear factor fs. The prediction methods based on the characteristic lengths are validated by the tests for composite joints with different parameters, and the results indicate that the methodology proposed in this paper can accurately and effectively predict failure loads as well as failure modes in composite pre-tightened tooth.