用四点剪切梁试件测得了钢纤维砼Ⅰ、Ⅱ复合型V形切口问题的临界断裂曲线,建立了断裂准则的经验公式,讨论了最大拉应变准则在V形切口问题中的应用. The critical fracture curves of composite V-notch of steel fiber 砼 I and II were measured with four-point shear beam specimens. The empirical formula of fracture criterion was established. The application of maximum tensile strain criterion in V-notch was discussed.