Experimental Study On The Slag Removal Effect Of Raise Boring Machine In Inclined Shaft With 20°～35°

The raise boring machine has good hole forming quality,high boring effect and high degree of mechanization.It is an important technology in the field of underground engineering.At present,there are few engineering examples of the raise method for the construction conditions of small inclination angles less than 45°.Therefore,for the purpose of expanding the application range of raise well construction,it is very necessary to study the construction feasibility of raise boring rigs under small dip angle conditions.In this thesis,the feasibility of the slag discharge of the raise rig under the condition of 20°～35° is studied based on three factors: the lithology of the slag,the angle of the raise,and the displacement of the auxiliary slag discharge.The main tasks of this paper are:(1)By deriving the unsaturated mechanical equilibrium conditions of the slag in the static state,the evaluation formula suitable for raising slag slag discharge under the condition of 20°～35° is obtained;the modified Si Shi’s modified formula is suit-able for 20° Under the condition of ～35°,the slag slag is discharged from the raise hole reaming,and the critical starting speed of the slag-carrying water flow under dif-ferent conditions of the raising hole reaming boring under the condition of 20°～35° is obtained.(2)Using simulation analysis to simulate the movement of two kinds of slag states in the flow channel.Based on the DPM model,the slag discharge rate as a whole rises first and then decreases;under the VOF model,the slag discharge rate The slag velocity is uneven as a whole,and the volume distribution also becomes narrower and the length increases as the whole moves downward.(3)The three types of slag produced by the on-site expansion of the raise shaft are used as the research object to carry out slag discharge tests under different conditions.The test results show that the factors that affect the slag discharge effect of the 20°～35° inclined shaft raise rig reaming boring are the slag discharge angle,the type of slag and the drainage volume.When other conditions remain unchanged,the greater the slag discharge angle,the better the slag discharge effect;the larger the displacement,the better the slag discharge effect.Displacement affects slag cohesion,internal friction angle,buoyancy and hydrodynamic pressure during slag discharge;slag type affects slag cohesion to affect slag discharge effect;slag discharge inclination angle affects slag gravity along The component force in the direction of the well side affects the slag discharge effect.