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An internal explosion may cause severe damage to an underground and surface ground structures. The intensity of the blast plays a substantial role in the damage to the structures, the configuration of the structure, material properties, and geometry of materials. There are several ways for a structure to be protect against blast loads. A tunnel could be protected employing the protective layer, directly located on the top of the structure. The influence of utilizing a protective layer, made of geofoam could appease the adverse effects of an internal explosion and decline vibrations when it comes to the surface ground. The modeling procedure used the coupled Eulerian-Lagrangian in Abaqus/Explicit. Lagrangian elements have been used for modeling soil and reinforced tunnel and trinitrotoluene as Eulerian elements. Drucker-Prager plasticity, Holmquist-Johnson and Johnson-Cook plasticity models were simulated for the stress-strain response of soil, concrete, and reinforcement, respectively. In addition, Jones-Wilkins-Lee equation of state used for the pressure-volume relation of TNT. As the results show, while explosion waves scatter inside tunnel and penetrate among top layers of soil, soil and lining without a protective layer experienced severe deformation and blast waves influenced surface ground structures negatively. Indeed, the more charge weight, the more deformation on tunnel lining and structures. It is observed that increasing geofoam thickness worked up to a certain thickness and semi-circular geofoam section on top of the structure fulfilled expectations.

来源平台：GEOTECHNICAL AND GEOLOGICAL ENGINEERING