| Summary: | Includes abstract. === Includes bibliographical references (leaves 191-197). === Landmines are the epitome of the perfect soldier: always ready, never tiring. Landmines also do not choose their victims - it may very well be an armed and protected soldier or an innocent civilian who activates the detonator. As such, land mines have reached epidemic proportions in the Third World, affecting both combatants and civilians, whether they are on foot or in a vehicle. When stepping on an anti-personnel land mine, traumatic amputation of the foot, lower leg or upper leg is generally expected. However, an anti-vehicle landmine detonating underneath a vehicle can have equally as detrimental results, as the occupants of the vehicle are bound to sustain serious injuries to the lower extremities. These injuries can vary from being less life threatening to being fatal in some extreme cases. Anthropomorphic test devices have been developed and refined over the years to represent the occupant exposed to simulated land mine detonation and then to retrieve valuable technical information from the test data. In the present investigation a simplified aluminium surrogate lower leg was designed, manufactured and subjected to axial blast testing. In addition, a rubber layer representing the sole of a standard army combat boot was placed below the foot model in a separate series of blast tests. The main factors investigated in this study were the effect of varying the amount and positioning of the explosives and the attenuation produced by including the rubber sole layer. The blast tests were conducted using a horizontal ballistic pendulum, with the foot model placed axially in the pendulum. The disc shaped explosives of different mass was placed in the centre of the detonation plate and axially in line with the heel respectively to draw a comparison between the respective stresses induced in the lower leg. As expected, the stress recorded by the strain gauges placed on the lower leg was significantly higher when the explosives were positioned in line with the heel than when placed in the centre of the detonation plate. The same series of blast tests were performed with the rubber sole being included in the test setup. Alternating the positioning of the explosives did not yield a significant difference in induced stress. Investigation of the blast attenuation provided by the rubber layer showed that the peak stress is mitigated by approximately 70%, which was much greater than expected. An elementary analytical solution was performed as a preliminary validation of the experimental test results. Furthermore, a finite element model of the aluminium surrogate foot and the rubber layer was created and a numerical simulation of each blast test was executed. Material data for the aluminium and rubber obtained via Split-Hopkinson Pressure Bar testing were employed to construct the material models used in the finite element model. The results from the numerical simulations compare well to the experimental test results for the blast loading conditions where the rubber layer was excluded from the test setup. In the case where the rubber layer was included in the testing, the trend and shape of the stress graphs obtained from the numerical simulation results agrees with the stress curves recorded during the actual blast tests. However, the peak stresses recorded during the experimental blast tests are found to be significantly higher than the peak stresses yielded by the numerical simulations.
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