Relevance of the research is caused by the need to protect space technology against man-made debris. The main aim of the study is to justify the application of three-dimensional numerical method based on the Lagrangian approach in describing the behavior of a continuum and a probabilistic approach in solid body fragmentation under impact loading relative to the problem of protecting space and ground facilities by combined barriers when interacting with elongated strikers-rods. The methods used in the study: A computational experiment involving experimental data to verify the numerical results. The results: The probabilistic approach and the proposed numerical technique allow, from physical point of view, reproducing with sufficient accuracy the processes of penetration and multilayer barriers spaced by high-speed core elements in more complete three-dimensional formulation. The introduction of random distribution of strength behavior initial displacement form nominal value into a body physical and mechanical characteristics results in destruction probabilistic nature in this case. This corresponds to the experimental data. The efficiency of spaced and layered-spaced barriers, currently widely used as protecting devices, is related to instability, plastic deformation and rod destruction besides hydrodynamic and strength resistance. The totality of the processes results in nutation angles occurrence, deviation of velocity vector and rod residue and fragments as well as in decrease in depth of penetration into layered-spaced construction in comparison with an inflexible rod. In calculations the author simulates shrapnel fields and takes into account fragments interaction and their interaction with the elements of a multi-layer barrier. The results obtained allow optimizing the protection of objects of mass geometrical parameters. An important application of the proposed approach is to study the deformation, fracture and ways to protect pipelines from the explosion and impact.