Study On The Shaft Construction Technology Of Passing Through Water-rich And Extra Thick-loose Tertiary Gravel

Passing through the thick alluvium quickly and safely in shaft construction is a complex technical problem of domestic and overseas'underground engineering in nowadays.In the course of shaft construction , the rib and inflow issues from shaft restricted the shaft driving speed and directly affected the process of mine. Based on return air shaft construction in Chen Jia-gou mine ,This paper gave comprehensive summary of the concept of thick alluvium and the classification of Shaft Sinking method,and analyzed the advantages and disadvantages of various methods and adapting to the conditions.To understand the geographic location, climatic characteristics, mine geological conditions, production layout, and the location of the return air shaft of Chen Jia gou mine, mastered the key geological conditions and hydrological conditions of location of the borehole and highlights explanation geological features of extra thick and loosely Tertiary strata complemented the exploration.Based on study, demonstration and feasibility analysis to alternate construction plan and considering safety, reducing project cost, ensuring duration and so on, sinking method has decided to be main methods used in construction of shaft Chen Jia-gou mine.In order to ensure common drilling method to rapidly adapt thick layers, this paper enhanced grouting technology research, analyzed grouting mechanismsand, discussed the basic elements and basic equations of the permeability grouting. Focusing on the grouting parameters including spread of slurry, injection pressure, grout injection rate, etc.When shaft returned air passed through the extra thick and loosely strata of quaternary and tertiary,speed excavation and masonry is main mathod to shorten process in exposing surrounding rock, taking grouting in advance range to water shut off, installing aqueduct at centralizing water point to control direction and flow of water,constracting centralized aqueduct to water conduction and pressure relief, realizing common sinking technique and comprehensive water control carried out simultaneously.Twice reinforcement technology for permanet support guarantee finished shaft according with design requirements and production needs.The study concluded that one section height controled between 0.5~1.2m from driving and support, Changed the original drainage using bucket with waste rock as an independent drainage Configuring a dedicated drainage system, Intensive sheet pile for temporary support can control quick sand flowed in a section height.