提高引黄保证率的微差爆破开槽方法研究

Research on the Method of Milisecond Blasting Slotting to Improve the Guarantee Rate of Yellow River Diversion

小浪底水库运用后,由于上游水沙条件的改变,黄河下游的河型处于剧烈变化之中,常导致引水口脱溜,引黄取水保证率常处于较低水平。采用微差爆破开槽的方法,可以保证河道主流和闸门之间的引水渠畅通,是提高游荡性河段的引水闸门引水保证率的一种有效方法。该方法首先用爆破形成可以冲开的最小引槽,然后引水冲刷,形成需要的闸前引水渠。试验表明,用最大一次起爆药量,可以控制爆破影响范围,爆破使土体液化的单向水平距离,约为爆破深度的10倍。用爆破方法可以快速形成成型的引槽。爆破不仅不会把成型槽周围泥沙压实,还会通过细沙的回填分选效应,使成型槽周围泥沙更易起动。

After the application of Xiaolangdi reservoir, because of the change of water and sand conditions, the downriver type of Yellow River is in the movement strongly that causes the departure of irrigating gate and the rate of guarantee always keeps the low level. Once the method of milisecond blasting slotting is put into use, the main stream and the leading river will flow smoothly, which is an effective way to improve the guarantee rate of wandering reach. Its principle is to blow up a small notch then wash out with water so as to form the irrigating channel before the gate. The experiment shows that the quantity of detonator can influence the bound. In other word, the unilateral horizontal distance is ten times of the depth of explosion. The method can make the notch quickly and presses the sand and mud around the notch and it is easy to jump-start through the backfill of silver sand.