Research on monitoring overpressure of car bombs

This paper aims to introduce the authors' research on the regularity of the overpressure distribution when a vehicle is exploded. In our experimental tests, we have tested the value of the overpressure produced by different amounts of explosives both in or out of a vehicle. The testing system consists of piezoelectricity-pressure transducer, DHF-4 charge amplifier, TEK TDS654C oscillograph and high impedance coaxial-cable. The experimental results show that, when vehicles are exploded, the overpressure would soon be getting attenuated quickly with the pressure near the doors being evidently higher than at the back of the car, the experiments also prove that overpressure outside the vehicles is also relatively higher than that in the open air. With the former being about 1.0-2.2 times higher than the latter,which proves that the reflection of shock wave is actually more evident than the restriction effect. On the basis of data analysis, we have discovered from the experiment the damage radius for human being and the least safety distance of shock wave to human body, which can be taken as a reference to dealing with car-blast accidents. At the same time, the reflection of blast wave cannot be neglected, which can be seen from the truck's test, the overpressure is also proved higher than explosive exploded in free air.