The utility model provides a gather ability explosive post for construction of tunnel smooth blasting processes out two at the both ends of PVC pipe earlier has the symmetrical special -shaped PVC pipe of its formation of fan -shaped recess messenger, sets up mark A, C, D, B, F, E point on the cross section of special -shaped PVC pipe, wherein the fan -shaped recess that encloses of C -> A -> E point be called first gathering can the cave, fan -shaped recess that the D -> B -> F point encloses is called that the second gathers can the cave, first gather can the cave angle CAE with the angle DBF that the second gathers the ability cave all is not more than 45, 16mm is no less than to the width that A put between the B point, along a first vertical isometric hookup PVC connecting pipe that gathers the ability cave, the 2nd PVC connecting pipe of vertical isometric hookup that gathers the ability cave along the second, to roll up to fill with the same emulsion explosive of special -shapedPVC pipe cross sectional shape and gather ability explosive post intraductal the formation promptly of whole special -shaped PVC, can improve tunnel smooth blasting effect, save because of backbreaking or owing to dig engineering volume and the expense that increases, reduction of erection time.