The invention discloses an
immersed tube tunnel foundation reinforcing structure and a construction method, and relates to the technical field of foundation reinforcement, the
immersed tube tunnel foundation reinforcing structure comprises a foundation and a plurality of gravel piles, the gravel piles penetrate through the foundation, each gravel
pile comprises a geosynthetic material, first gravel and a reinforcing piece, and the geosynthetic materials are arranged in a surrounding mode to form a hollow columnar structure; the
geosynthetics arranged in the surrounding mode are filled with first broken stones, and the reinforcing pieces are arranged in the
geosynthetics arranged in the surrounding mode; and the
gabion layer and the second gravel are arranged on the gravel
pile in the height direction, the
gabion layer is arranged above the gravel
pile and connected with the reinforcing piece, and the
gabion layer is filled with the second gravel. Therefore, the gravel piles penetrate through the foundation, and the gabion layer is arranged above the gravel piles and is connected with the reinforcers, so that the risks of
instability and non-uniform settlement of the immersed tunnel foundation under the action of strong shock or load can be reduced, and the
bearing capacity and rigidity of the immersed tunnel foundation are remarkably improved; and the anti-seismic property and the stability of the immersed tunnel foundation can be improved.