Abstract: To solve blasting effect of a long tunnel with thick overburden in the fractured rock mass, the Bashkorgan No.2 tunnel of Xinjiang Urumqi-Yuli Highway PPP Project is presented as the research object. The energy-accumulating hydraulic blasting method which is based on the principles of the cumulative effect were used to overcome difficulties and challenges during the fractured rock mass tunneling. The blasting parameters and the production process of the energy-accumulating tube were determined. The effects of the dust reduction, the transverse section shaping, the surrounding rock disturbance, the cost reduction and benefit enhancement are studied by using the method of the field measurement. The results show that, compared with the smooth blasting method, the peak value of the dust concentration produced by the energy-accumulating hydraulic blasting method is about 11.23mg/m³, and the time of ventilation and dust removal is saved by 50%. As far as the Class III surrounding rock is concerned, both blasting methods are applicable. The advantages of the energy-accumulating hydraulic blasting method smooth effect are not obvious; For the Class IV surrounding rock (abundant joint fissure) and the Class IV surrounding rock (f80 fault), the maximum overbreak value of the energy-accumulating hydraulic blasting method is controlled at 7cm and 9cm, respectively. The overbreak and underbreak values are significantly improved. The use of the energy-accumulating hydraulic blasting method can effectively reduce the blasting vibration and the disturbance of surrounding rock. The maximum vibration speed is 0.78cm/s. The cost saving of the single tunnel can be 9.1216 million yuan.

Key words: Energy-Accumulating Hydraulic Blasting Method, Deeply Buried Tunnel, Fractured Rock Mass, Overbreak and Underbreak, Economic Performance, Bashkorgan No.2 Tunnel