半椭圆表面裂纹是金属结构中比较常见的一种缺陷，在外界因素作用下容易发生扩展，甚至导致结构破坏，而采用纤维增强复合材料( FRP) 等新材料对其进行加固维修可以大幅度提高其使用寿命．文中应用Abaqus 有限元软件，对受拉 FRP 加固 X80 钢板中半椭圆表面裂纹的应力强度因子进行数值分析，并给出了加固条件下应力强度因子的半经验表达式．结果表明，在均匀拉伸载荷作用下，对于应力强度因子及加固效果，裂纹形状比的影响较大，裂纹相对深度有一定影响．

Semi- elliptic surface crack is a common defect in metal structures,which is easy to propagate under the effects of external factors and may even result in the damage of the structures.The service life of the damaged struc-tures can be greatly extended by using the fiber- reinforced polymer (FRP) to strengthen and repair them.In this paper,the finite element software Abaqus is employed to numerically analyze the stress intensity factor (SIF) of the semi- elliptic surface crack in the X80 steel plate strengthened with FRP under tensile load,and the semi- empirical expression of the SIF is obtained.The results show that,under the uniform tensile load,the crack shape ratio has a greater effect on the SIF as well as on the reinforcement effect,and the relative crack depth also affects them to a certain degree.