Analytical J-integral model for mode-I cracks in ductile materials with three-dimensional constraints

•Proposed a semi-analytic J-integral model with three-dimensional constraints.•Verified the accuracy of the proposed model using finite element analysis.•Determined the geometric independence of the proposed model.•Analyzed the influence of the constitutive parameters on the proposed model.•The proposed model is simple, accurate, and well-suited to engineering practice.