From May 26, 2017 to June 25, 2017, No.4 drilling team of Raise Boring Branch successfully completed the construction of 07# manhole at 2642m ,08# manhole at 2642m , and No.1211 cutting raise, totally 3.5 raises,in Xitieshan project, including 204.9 meters of guide hole, 157.4 meters of reaming , the potholing quality is good, and the deviation under control with rate within 1%. In the case of frequent equipment transshipment, completion of such volume in 1 months with safety, high efficiency and quality, has refreshed the best record of raise-boring branch in the first half of 2017.
Xitieshan Project planned to construct 2 shafts in June, 4 operators of No.4 drilling team closely followed the construction plan, worked overtime to complete the task ahead of schedule. The early completion of this task not only greatly improved the underground air quality, but also improved underground emergency safe-haven system. Meanwhile, the shortening of the schedule has laid a good foundation for the smooth connection with next operation, which further advances the overall construction progress.
Under complicated geological condition, it is difficult to meet the requirements with conventional methods, and using raise boring machine has several advantages compared with hand excavation, such as low safety risk, low cost, high engineering quality and rapid construction speed. It is an important development trend in the future to take some effective construction techniques and means to complete the raise boring tasks successfully.
