Abstract：Charged with air cushion，the blasting mechanism of smooth blasting with soft cushion charging construction is studied. Namely，the soft cushion can not only decrease the pressure of explosion shock waves and explosive gases in order to reduce the shock compress breaking on hole-wall，but also can extend the action time of explosive gas-pressure and improve the quality of breaking cracks of smooth blasting under the quasi-static pressure of explosive gases. According to the requirements of smooth blasting，axial decoupling coefficients of charging construction with air soft cushion are analyzed. Correspondingly，the theoretical calculation formulas are presented. Finally，the axial decoupling coefficient values of smooth blasting in some rocks with air layer are calculated，and the air soft cushion charging construction is used in engineering practice of smooth blasting. The results show that air soft cushion is an effective smooth blasting charging construction.
