Prediction Of Shockwave Overpressure Under The Explosion Of Vehicle Bomb And Its Application

Explosive has been major arms for terrorist activities more and more frequently because of the seriously damages and big losses it may cause and that is a big threat for peace and tranquility of the international community.So, load effect of the explosive and the subject research of related field are extensively concerned for the researchers at home and abroad. This thesis not only writed a visualization program for computer aided structure design of anti-explosion on the basic theory of explosion mechanics and such many related literatures but also simulated the propagating laws of explosion shockwave and the load it acted on the building when the wave meets the building with the help of ANSYS/LS-DYNA software. The main research work and innovation achievements include the following respects:(1) The propagating laws of explosion load and empirical formulas for blast wave parameters are researched, and then, a software to visualized display the pressure and pulse of structure surface under explosion load and set the guardrail for anti-explosion and disaster reduction is developed. It got a very fine goodness of fit after the software calculated results and experience formula calculation results were compared which proof the reliabilityof the codes.(2) The propagation law and characteristics of detonation wave which is generated by the explosion of car bomb in the semi-infinite air domain close to the surface are simulated through the display dynamic nonlinear finite element analysis software ANSYS/LS-DYNA.All of this are on basic of the comprehensive of fluid computational mechanics, structural dynamics and explosion mechanics and the related concept. The effect of mesh size in the numerical calculation is also analyzed. It shows that the simulation of explosion by means of Finite element dynamic analysis software LS-DYNA is feasible after comparation the results of the finite element model with high accuracy grid calculation and close surface explosion experience formula calculation.(3) Numerical analysis model of car bomb blast wave spread to a single building was set up,and then, the propagation process after explosion shockwave meets buildings in the air was simulated,in the mean time, the exploded load distribution on the surface of the building was studied.(4) At last, the propagation law was simulated when the blast wall was build outside the building to learn the block function to shock wave and it’Protection.The effect of the blast wall’height and the distance between blast walls and the building for the protection was analysed by changing parameters of model.