FINITE ELEMENT ANALYSIS OF FATIGUE CRACK PROPAGATION ON TRAFFIC SINGAL SUPPORT STRUCTURES

In order to solve the problem of the fatigue crack propagation on traffic signal support structures, the ANSYS software is used to model the previous static and the fatigue tests on a signal support structure. The finite element (FE) results are compared with the test results. The results show that the maximum Mises stress on the steel tube is 413.7 MPa in the static model. The FE results are close to the test results. The △K_Ⅱ and the △K_Ⅲ values at the deepest point are very small. The △K_eff values are almost equivalent to the △K_Ⅰ values. The fatigue life is dominated by the △K_Ⅰ value. The △K_Ⅰ values for the points further away from the crack ends present M shape. The △K_Ⅰ values calculated by the Bowness equation are larger than those obtained by the FE method. It is conservative to predict the fatigue life for the welded tube-to-transverse end plates used in signal support structures.