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The current paper is concerned with testing the efficiency of a uninstrumented method in assessing granular porous media capacity to mitigate blast impulse. A thin plate constant deformation test was carried out based on the findings obtained throughout blast-structure interaction phenomena. The proposed test requires only post-test measured data and no test instrumentation is needed. The test protocol under scrutiny consists of a short series of 200 g TNT charge detonations at 1000 mm distance from the tested structures. All test results have shown impulse mitigation. The findings obtained in the test under scrutiny tally those in the pendulum test. The final section of the current article is concerned with the improvement and shortcomings of the test developed.

The paper deals with constitutive models determination for a group of high entropy materials (coded Bl-x). The procedure includes the following steps: experimental determination of mechanical characteristics for quasi-static domain through compression tests, correction of experimental data of quasi-static tests using numerical simulation, acquisition of experimental data obtained on the Split Hopkinson Pressure Bars and their simulated interpretation. Using the processed data, the constitutive patterns of the materials under investigation are drawn. The experimental data correction for quasi-static tests performed using numerical simulation involves drawing the engineering stress/strain diagram, the transition to the plastic characteristic diagram in the hypothesis of perfectly cylindrical shape of the specimen throughout the test, simulation of the compression deformation process in the presence of friction force on the end specimen surfaces and the correction of the characteristic plastic diagram using the calculated error. Dynamic data obtained on Split Hopkinson Pressure Bar were interpreted using a methodology previously published. Experimental data under real conditions are compared with data obtained by numerical simulation on an elasto-plastic model. The viscous component of the dynamic response is the difference between the real and simulated on the elasto-plastic model responses.

The issues related to mechanical resistance of solid rocket propellants, which can appear during storage or handling of the launching system, are considered to directly influence the burning performance. Thus, in this study, four new types of composite rocket propellants, based on an environmentally friendly oxidizer (phase-stabilized ammonium nitrate), a metallic fuel (aluminium), and a "green" polyurethane-based binder (synthesized from an oligomeric isocyanate and a blend of polyester-polyols obtained through the catalytic degradation of polyethylene terephthalate), were subjected to compression mechanical analysis in order to highlight the importance of the binder on the response given by the tested materials subjected to compressive loads. The samples showed remarkable mechanical performances, the experiments allowing us also to determine the influence of the binder composition and fuel granulation on mechanical properties of the composite propellant.