The numerical investigation of shear macrofracture formation is presented. The modifications of stress-strain state of the elastic material under of shear strain propagation on the line segments are considered. The shear lines are modeled by cuts with conditions on them providing the possibility of appearing of discontinuities in shear displacements. A finite element method is used for numerical modeling this problem. The contour lines of maximum shear stresses in the domain for the different load steps are constructed.