Abstract: The technical difficulty of mine geotechnical engineering under complex working conditions such as soilrock combination,blasting construction and underlying Goaf is often greater,which is one of the key research directions in the field of geotechnical engineering.Based on the Green Mine Construction Project of Sanshandao Gold Mine,the research on water stop technology of special support for super deep mining pit is carried out.After systematic research and scientific calculation,the composite supporting scheme of the footlifting occlusive pile+highpressure jetgrouted anchor cable is put forward,and no water leakage occurs in the supporting structure after the implementation,under the condition that the peak value of particle vibration velocity exceeds 8 cm/s frequently,the maximum displacement of pile body is 17.5 mm,which meets the safety requirement.The proposal and implementation of the compound supporting scheme of footlifting bitting pile+highpressure Rotary spray anchor cable not only enriches the design theory and construction technology of mine geotechnical engineering,but also provides reference for similar projects.

Key words: Mine geotechnical engineering,Superdeep mining pit,Footlifting occlusive pile,Watertight support structure