This pa per has analyzed shock wave cut role of gear wave wall to explode in air. As a r esult,the gear wave wall of certain alti tude and thichness repairing around the blast source can weaken the pressure of peak value 20%~30% away from air shock w ave after the wall.At the same time,the interaction course between shock wave an d gear wave wall has been calculated wit h numerical simulation method, and the e xplosive site initial development of bar rier around the blast source,as well as entire sprea...