Research of raise boring technology on constructing nearly 300m deep shaft underground in iron mine

Heilongshan Iron Mine designed to constructed 3nearly 300m deep shafts,the raise boring method was used for safe and efficient construction.It's the first time that raise boring machine constructs nearly 300m deep shaft underground in China,although it has been mature in constrcting within 100m shallow shaft.The use of the BMC300 raise boring machine is based on the analysis of rock compressive strength and loose coefficient,base on the pilot thrus,reaming thrust,pilot torque and reaming torque.The successful completion of this construction is depedent on the optimization of the construction program and the strict control of the parameters,the key techniques such as reasonable arrangement of stabilizers and control of deflection has also been carefully studied,the deflection rate is about 0.5%.The practice shows that the use of raise boring method in deep shaft underground is worth learning from and promoting.