Research on the shear failure load of composite pretightened tooth connections by the characteristic lengths

In the conventional methods, the shear failure load of composite pretightened tooth connections is determined by experiment. To determine the shear failure load of the composite pretightened tooth connection without performing experiments, a method based on the characteristic lengths is presented in this paper. This method involves three steps: first, the characteristic lengths of the composite are determined; second, the stress distribution of the composite joint is analyzed by the use of a finite element method; finally, the failure load is predicted by the stress distribution of the characteristic length and failure criterion. The failure loads based on the characteristic lengths are validated by the test results for composite joints with different parameters. In comparison with the experimental data, this method provides higher magnitudes of failure load with a difference of <11% of the test value, except one with 11.6%. Good agreement was observed among the results of the present numerical method and the test. The method in the present work can be directly used in the design of pretightened tooth connections.