The invention discloses a deep-hole backward grouting and water-blocking construction method for an
igneous rock water-rich fault. An advance exploratory drilling technology is adopted to prove a
fracture zone of the water-rich fault, after deep-hole backward advanced pre-grouting and primary water blocking, tunneling construction is quickly conducted to pass through the
fracture zone of the fault, and in a tunnel area of a water-rich section, full-face deep-hole backward little
tremie grouting and secondary water blocking is adopted. According to the characteristics that the
fracture zone ofthe
igneous rock fault is large in fracture aperture and high in
connectivity, the deep-hole backward grouting method is adopted to change the way that a little
tremie conducts segmented grouting at the positions of grouting holes from far to near in the order of I, II, III, IV......, the
grout on the upper stage is deposited and solidified to achieve an enhancing effect on deposition and solidification of the
grout on the next stage, finally, cracks are sufficiently filled with the
grout, the water-blocking aim is achieved, the problem that in the prior art,
igneous rock tunnel construction is conducted to pass through the water-rich fault, water is difficult to block is solved, and the full-face deep-hole backward grouting method is provided for the difficulty of grouting and water blocking in the process that
tunnel construction is conducted to pass through the fracture zone of the water-rich fault in the igneous rock.