The fatiguebreakage is one important of damage style in mechanic fractures. Forecasting structure fatigue life is very important.
疲劳破坏是机械结构的主要破坏形式之一，准确预测机械结构工作疲劳寿命至关重要。
2
Fork failure of a forklift truck mainly takes a form of plastic deformation exceeding allowable limit, fragile breakage and early stage fatiguebreakage.
叉车货叉失效方式主要表现为塑性变形超差，脆性断裂和早期疲劳断裂。
3
It is found that inherent frequencies are much larger than pumping frequencies and resonance cannot emerge before and after optimization. Fatiguebreakage is caused by overload mainly.