Power takeoff fatigue durability evaluation method based on bench test and whole vehicle load test

The invention discloses a power takeoff fatigue durability evaluation method based on a bench test and a whole vehicle load test, and belongs to the technical field of automobile component fatigue durability, and the method comprises the steps: obtaining a failure cycle number, carrying out the statistical analysis, and obtaining the power takeoff intensity distribution and 50% S-N curve slope; a transmission shaft torque testing device is built, and strain-torque relation calibration is carried out; torque and rotating speed signals of the transmission shaft are tested in a test field, and a torque-rotating turn number spectrum is compiled; converting a rack endurance test result and a test field test result to a corresponding number of rotation turns under the reference torque; and calculating power takeoff strength distribution and test field load distribution, and evaluating the failure risk of the power takeoff by adopting a stress-strength interference model. According to the method, the strength distri