九松山隧道岩塞爆破的技术创新

北京第九水厂首部工程──密云水库九松山隧道水下岩塞爆破于１９９４年１０月２８日进行，水深３６ｍ，是中国最大水深的塞爆。由于这一工程的特殊重要性，进行了三年多的试验研究，在爆破设计、水下测量、防渗堵漏、动态观测、岩碴处理和钻孔装药等方面都有创新，塞口成型尺寸准确、围岩稳定在类似的工程中是最好的，多项技术达到国际先进水平，特别是以综合的现代技术，准确掌握塞爆中石碴、水流、空气三者的动态过程，圆满实现了“洞内集碴，控制出流”这一独特的塞爆岩碴处理技术，控制挟碴水流以小于１ｍ￣３／ｓ的流量慢慢泄出洞外，省去积碴坑、出口排洪建筑和拆迁等大量资金，获得了巨大的经济和社会效益。

THE NEW TECHNIC ADVANCE OF ROCK PLUG BLASTING UNDER WATER OF JIUSONGSHAN TUNNEL

The under-water rock plug blasting of the Jiusongshan tunnel of Miyun reservoir for Beijing No.9 Water Works,was carried out on Oct.28,1994.The rock plug,36m deep,is the deepest rock plug under water in China.Due to the special importance of the project to the capital,the experimental research had been undertaken for over three years.The breakthrough and new innovation had been achieved in blasting design,under-water survey,seepage control,dynamic observation,rock spoils treatment and borehole loading.The accurat siz,smooth shape and the stability surrounding rock is the best in comparison with the similar projects,and several techniques had met the international standards,especially,with the comprehensive modem techniques precisely controlling the dynamic process occured among rock spoils,water and air flow within the tunnel,the initiative rock spoils treatment technique──"collecting the fragments within the tunnel controlling the out-flow" was perfectly carried out,the discharge flow of the tunnel was less than 1m￣3/s.The fund for pit for heap fragments,the channel and pool for release the great discharge flow of tunnel,demolishment,etc.were eliminated.This technology has a great economic and social benefit.