Analysis on fatigue failure of large span vertical lift gate

Abstract

   The large span vertical lift gate is completed base on welds which conect each steel structural member in both the factory and the fieldwork. If the welds contain some defects under the stress concentration, fatigue failure in the welding line is possibility happened without a large number of pressure cycle. Therefore, anlysis on fatigue failure of large span vertical lift gate working in two direction is nessesary. This paper has indicated one of a dangerous join of gate by FEM modal to consider the fatigue failure. In addition, research has pointed these certain types of weld defects can directly develop fatigue cracking