The invention discloses a large-
diameter offshore wind power rock-socketed single
pile excavating method. The large-
diameter offshore wind power rock-socketed single
pile excavating method comprises the following steps that immersion of a
pilot shaft
pile casing is carried out; a
petroleum drilling
machine is adopted for excavating a
pilot shaft through the
pilot shaft pile casing; a geological
drill is adopted for drilling two to three rings of main blast holes and one ring of outline blast holes, and a casing off hole is lowered down; a dedicated CO2
phase change expansion crack
pipe is mounted, the interiors of the main blast holes are mounted in a segmented manner, and the interiors of the outline blast holes are continuously mounted; a blast network is connected; a rock-socketed single pile steel pile casing is lowered down; mud and
weathering sand between the pilot shaft pile casing and the rock-socketed single pile steel pile casing are sucked away; the pilot shaft pile casing and a drilling casing pile are pulled out;
underwater slag cleaning is carried out; and concrete is poured to form a rock-socketed single pile foundation.
Pilot shaft mechanical excavating and CO2 expansion
rock breaking and expanded excavating are combined, the technical problem that a 2-4mm-
diameter petroleum drilling
machine and a common geological
drill are used for finishing excavating of an offshore rock-socketed single pile foundation with the diameter being 8 to 10 m and above can be solved, the expansion pressure generated by a CO2
phase change is controllable, the explosion
impact waves and the vibration speed are small, and the method is economic and environment-friendly.