Abstract Analysis of anchor bolts problem in concrete structures is made through the application of finite element method and a granular microcracked model. This analysis is based on the principles of linear elastic fracture mechanics (LEFM) applied at the level of the matrix and takes both material's heterogeneity and pre-existing microcracks into consideration. Numerical results concerning crack trajectory, load-displacement curve and K-a curve are presented. Comparison is made between the results for the specimen composed of a granular microcracked material and those obtained through the application of LEFM to the same specimen composed of a homogeneous material with one crack. The numerical results are also compared with experimental ones. The influences of the granular structure of concrete and pre-existing microcracks on the crack trajectories and stability of crack propagation are discussed. Keywords: Analysis of anchor bolts, Pull-out, Material's heterogeneity, Microcracks, Linear elastic fracture mechanics, Numerical simulation.