At present, pneumatic downthehole hammer type singleboom multifunction drills, which have such disadvantages as high cost, low efficiency, slow speed and heavy pollution, are generally used to drill the boreholes of fullface advance grouting. For the grouting borehole drilling in Jiaozhou Bay subsea tunnel in Qingdao, 3boom hydraulic rockdrilling jumbos are used due to their large working scopes, high flexibility, low dust pollution, high safety and civilization level, high efficiency of hydraulic impact drills and specialized management. 3boom hydraulic rockdrilling jumbos not only can achieve rapid blasting hole drilling in tunnel excavation, but also can achieve high speed, high quality, high safety and high efficiency borehole drilling in fullface deep hole advance grouting under poor geological conditions.