Abstract: In order to study the crack initiation life of construction rim, a finite element model was established based on the bending bench test of an enterprise’s construction rim. The finite element software ANSYS-WORKBENCH was used to carry out the finite element static stress analysis, and on this basis, the fatigue life cloud diagram of the steel ring was obtained by predicting the crack initiation life of the steel ring with the life simulation software Ncode, finally, the crack of the steel ring can be detected in real time by using the nondestructive testing method of acoustic emission, and the initial crack of the steel ring can be stopped by the control bench test machine of acoustic emission system when the initial crack of the steel ring appears, which were compared with the simulation value.