根据起重机出现的裂纹数量和严重程度,通过断裂力学推算出裂纹的扩展公式,结合起重机箱形梁应力谱和裂纹的扩展公式,推算出起重机的使用寿命。应用损伤力学公式估算起重机的使用寿命,有利于企业对设备进行维修和更换,保证施工安全。 According to the number and severity of cracks in the crane, the crack propagation formula is deduced by the fracture mechanics. The stress distribution and the crack propagation formula of the crane box beam are used to calculate the service life of the crane. Applying the damage mechanics formula to estimate the service life of the crane will help enterprises to repair and replace the equipment and ensure the construction safety.