超前预注浆堵水在万家寨引黄工程支(北)01洞涌水段施工中的应用

北干线支（北）01隧洞段由于地质情况复杂。涌水量较大，采用深孔分段式超前预注浆施工，使洞内涌水得以控制，并顺利通过了该地段。

Pilot Pre-grout for Stopping Water in Blow Section of Tunnel, Wanjiazhai YRDP(Yellow River Diversion Project)

The downstream side of tunnel NO(01),lateral(the north),the north main line,Wanjiazhai YRDP surrounding rock is cataclastic dolomitic limestone,wormkalk belonging to the upper cambrian series,camb rian sys-tem,where the discharge of blow is so high,about 300cubic meters per hour ,that the measure,the pilot pre -gro uting for stopping water simply must to be t aken,As a result of taking this measu re,more than 90%of the discharge of t he blow had been reduced enabling the ex cavation passing through the blow se ction of the tunnel to be completed wi thout a hitch.That the matters introduced in this paper are briefly summarized as follows:grouting agent,cement g rout and water glass grout;grouting process,stage grouting from working face,e ach stage is less than 15meters;grou ting pressure,3.3kg /cm 2 (design value).Fig.1.and Fig.2show the layout of t he grouting holes.