三峡RCC围堰拆除爆破炮孔堵塞施工方案

Blast-hole stemming scheme for blasting demolition of RCC cofferdam for Three Gorges Project

三峡工程三期上游RCC围堰拆除爆破所用炮孔和药室采用专用刚性炮孔堵塞材料进行堵塞。这种堵塞材料的特殊组成和大流动性给其拌和及灌入水平炮孔(药室)带来一定困难,而炮孔和药室的分布则给其输送造成不便。本方案通过改变拌和投料顺序和在水平炮孔口插入弯管等技术措施,分别解决了拌和时材料粘附拌和机以及水平炮孔难以灌满等两大难题,而长距离管道输送则使该堵材的垂直和水平运输问题得到妥善解决。

All the blast-holes and charge chambers for the demolition of the upstream RCC cofferdam for the Phase-Ⅲ construction of Three Gorges Project are planned to be stemmed with a special rigid plugging material. However, the special composition and high fluidity of this kind of plugging material would bring some difficulties to the components mixing and the filling of the horizontal blast-holes and chambers, and the distribution of blast-holes and chambers would also make the conveyance of blast-hole-plugging material even more inconveniences. The scheme introduced herein has solved the problems from the adher- ence of the material to the mixer and the hard filling of the material into the horizontal blast-holes based on the technical measures of changing the material feeding sequence of the mixing and plugging bending tube into the mouth of the horizontal blasthole, and furthermore, the problem from the long distance horizontal and vertical conveyance of the material is adequately solved as well.