Abstract: To study the progressive collapse process of structures,a method to apply instantaneous load was adopted to simulate the progressivecollapse of a multi-story plane steel frame with a failed middlecolumn at the first story by using the large deformation and dynamic finiteelement software LS-DYNA. The analysis results show that the progressivecollapse resisting capacity of steel structures can be remarkably improvedby increasing the failure strain of the structural material.