Early warning method and device for fatigue failure of steel crane beam

The invention provides an early warning method and device for fatigue failure of a steel crane beam. The method comprises the following steps: forming a circular hole with a second size and a fatigue crack with a third size on a steel plate with a first size; fixing the steel plate at a preset position of a lower flange of the crane beam; when the steel plate is fixed, applying a longitudinal pretension force with a preset size to the steel plate; arranging crack monitoring equipment, and monitoring the fatigue crack on the steel plate in real time through the crack monitoring equipment; and when the length of the fatigue crack on the steel plate is greater than or equal to a preset length threshold, sending out alarm information. By applying the early warning method and device provided by the invention, early warning can be carried out on the fatigue failure of the crane beam. 本发明提供了一种钢吊车梁疲劳破坏的预警方法及装置。其中的方法包括：在具有第一尺寸的钢板上形成具有第二尺寸的圆孔和具有第三尺寸的疲劳裂纹；将所述钢板固定在吊车梁的下翼缘的预设位置；在固定所述钢板时，对所述钢板施加预设大小的纵向预拉力；设置裂缝监测设备，并通过所述裂缝监