Abstract: In order to investigate the influence of shell thickness of explosives on damage effect in concretes, the explosives with different thickness shells and concrete targets with non-boundary effect were designed. Experimental results show that the craters volume caused by explosives with thin shell is more than the craters volume produced by no shell explosives, but the sizes of craters decrease with shell thickness increasing. The fragmentized degree of shells descends with shell thickness increasing. The ratios of the energy of shock waves in air to total energy of explosives are gained by measuring overpressure of shock waves and experiential formula.