  Topological mechanical metamaterials have demonstrated exotic and robust
mechanical properties which led to promising engineering applications. One of
such properties is the focusing of stress at the interface connecting domains
of topological Maxwell lattices of opposite topological polarizations, which
protects the bulk of the material against fracturing. Here we generalize this
theory to non-ideal Maxwell lattices, incorporate real material features that
leads to interactions beyond previous ideal models. By quantitative analysis of
stress distributions of topological Maxwell lattices with self-stress
interfaces theoretically and computationally, we propose a design rule that
minimizes stress in the bulk of the material. This design rule can guide the
realization of stress focusing and fracturing protection in real materials.
