The Qipanyan pluton locates in Jiangshuihe village-Qipanyan village,Mentougou area, Beijing, which has a irregular ellipse in plane shape, extension ofnorthwest and trend of northeast.

This paper systematically advances a set of methods and formulas on the basis of model experiment, which can be applied to determining rational parameter of cutting underedge stone and caving unit distance of sublevel caving without sill pillar.

Combined with practical work and based upon analysis of advanced water prospecting advanced pre-grouting reinforcement scheme is proposed;at the same time practical construction technology is elaborated from construction of sealing batholite,reinforcement range of curtain grouting,embedment of pipe,grouting construction process and other aspects.

Combined with the projects generate situation,it introduces the action of sealing batholite in curtain grouting,analyses the decided of the construction planning of sealing batholite,represents the injecting technology and construction techniques of sealing batholite.

Combined with Laohugou tunnel project and according to the different underground water yielding,it builds the different sealing batholite,finishes the water stopping by using purdah injecting,and stops the leakage of the underground water,and this supplies theoretical reference and practical experiences to further extend the technique.