The Propagation Rules Of Shock Wave And The Dynamic Properties Of Buildings Under The Effect Of Vehicle Bombs

With the spread of the terrorism, the explosives are more and more often used by the terrorists. The terrorist explosion activities have seriously threatened to the international society's peace and have been a cancer which does a lot of harm to the national security and the social stability. The vehicle bombs are especially popular among international terrorists due to massively charge powders, high success ratio and serious destruction. To meet the need of a national defense research project, because of the frequent occurring of terrorist vehicle bombs and their high destructiveness, therefore, this paper studies the propagation rules of shock wave. This paves the way for more important experimental research later. Based on the previous research results, the following researches are done in this paper by numerical simulation.1, Using ALE algorithm and the JWL state equation for the product of explosive detonation, the propagation rules of shock wave above the ground without obstacles(which can be regarded as the half infinity space) induced by vehicle bombs has been studied. The three-dimensional model is set up using ANSYS, and program LS-DYNA3D is used to calculate. The numerical simulation result is compared with the empirical formula calculating results, and the research results suggest that the overpressure basically coincides with them.2, The propagation rules of shock wave caused by vehicle bombs in an urban environment is analyzed, and the numerical simulation of which the shock wave flows around an obstacle is conducted. The initial development of three-dimensional explosive field and the around-flow behavior with an obstacle around an explosive source are obtained. By using post-processing software LS-PREPOST to give a visual revelation to the around-flow course, the results suggest that the around-flow phenomena coincide with the law of physics. In addition, the influence of the street junctions on blast wave impulses and pressure produced by vehicle bombs are considered.3. As a kind of explosion near the surface, the vehicle bombs can produce air-shock wave and seismic wave. In the epicenter of explosion, the seismic waveintensity is very big. The dynamic responses of buildings both caused by air-shock wave only and caused by both air-shock wave and seismic wave have been studied separately, from which it can been seen that the influence of seismic wave cannot be neglected because the buildings are near to the centre of bombing.In the end, the content of this paper has been summarized and some problems, which need further study, have been proposed.