A combined ALE-cohesive fracture approach for the arbitrary crack growth analysis

•FE model able to simulate the arbitrary crack propagation with mesh adaptation process.•Moving mesh technique employed to reduce the mesh dependency issues.•Cohesive crack approach used to describe the nonlinear fracture process.•Numerical applications performed with different fracture conditions and multiple crack propagation.•Comparisons with experiments assess the reliable application to quasi-brittle materials. This work introduces an advanced numerical model, based on a cohesive zone approach and the moving mesh technique, for simulating fracture propagation in quasi-brittle materials. The proposed procedure involves two stages: first, a mesh boundary representing the crack is selected and aligned with the crack growth direction by using the Arbitrary Lagrangian-Eulerian (ALE) methodology; next, a zero-thickness interface cohesive element, equipped with a traction-separation law, is adaptively inserted along the previously selected mesh boundary, in order to describe the nonlinear fracture process. The proposed model allows for multiple crack onset and propagation without requiring mesh-updated procedures and sensibly reduces the well-known mesh dependency issues of the standard discrete fracture approaches. Numerical analyses of mixed-mode fracture in concrete specimens are performed and suitable comparisons with experiments show the effectiveness and reliability of the proposed model in predicting arbitrary crack growth.