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An account is given of some principal observations made from a series of experiments in which metal cylindrical shells were subjected to lateral explosion impact by different TNT charge mass and stand-off distance. These cylindrical shells were filled with water in order to identify the main effects produced by the fluid-structure interaction. In comparison, the explosion impact experiments of the empty cylindrical shells were also carried out. The effects of TNT charge mass, stand-off distance, cylindrical shell wall thickness and filled fluid (water) on perforation and deformation of metal cylindrical shells were discussed, which indicated that water increased the wall strength of the cylindrical shells under explosion impact loading, and the buckling deformation and perforation of the cylindrical shell was significantly influenced by the presence of the water; blast-resistant property of the tube under explosive impact loading of 200g TNT charge was much excellent; deformation and damage of empty cylindrical shell were more sensitive to stand-off distance changed. ALE finite element method was employed to simulate the deformations and damages of empty and water-filled cylindrical shells under explosion impact loading. The experimental and computational results are in agreement, showing the validity of the computational scheme in complex fluid-structure interaction problems involving metal materials subjected to explosion impact. The results show that internal pressure of water will increase when subjecting to impact loading, the anti-blast ability of tube structure is significantly enhanced.

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When subjected to the dynamic load, the behavior of the structures is complex and makes it difficult to describe the process of the deformation. In the paper, an analytical model is presented to analyze the plastic deformation of the steel circular tubes. The aim of the research is to calculate the deflection and the deformation angle of the tubes. A series of assumptions are made to achieve the objective. During the research, we build a mathematical model for simply supported thin-walled metal tubes with finite length. At a specified distance above the tube, a TNT charge explodes and generates a plastic shock wave. The wave can be seen as uniformly distributed over the upper semicircle of the cross-section. The simplified Tresca yield domain can be used to describe the plastic flow of the circular tube. The yield domain together with the plastic flow law and other assumptions can finally lead to the solving of the deflection. In the end, tubes with different dimensions subjected to blast wave induced by the TNT charge are observed in experiments. Comparison shows that the numerical results agree well with experiment observations.

Large-scale experimental investigations were conducted on the flow structures and intensity of shock waves generated by the rupture of a high-pressure pipeline. In the experiments, the bursting of pipes was caused by an initial crack introduced on the upper center of the pipe. The crack velocity, pressure-time trace and explosion overpressure were measured. The intensity of the far-field explosion overpressure was estimated based on the extent of damage to buildings. The results demonstrated that the shock waves generated by a pipeline rupture indicate an extremely strong directional effect in the near-field, and their measured speeds were similar to the speeds calculated from theory. Not all of the gas energy participates in the explosion of a long pipeline, and an equation is established to calculate the gas energy involved in a pipeline blast. The TNT equivalency approach was used to calculate the explosion overpressure, and the impulse generated by the pipeline rupture and its applicability were discussed.