Quasi large-diameter pile formed by bunching plurality of small-diameter piles and construction method of quasi large-diameter pile

The invention discloses a quasi-large-diameter pile formed by bunching a plurality of small-diameter piles and a construction method of the quasi-large-diameter pile. The structure of the quasi-large-diameter pile comprises a plurality of foundation pile units with the same structures, wherein a group A of foundation pile units and a group B of foundation pile units are uniformly arranged at intervals to form the foundation pile unit, both the group A of foundation pile units and the group B of foundation pile units comprise concrete main bodies and steel bar cages, occluding grooves are formed in the outer sides of the steel bar cages, and the occluding grooves in the group A of foundation pile units and the group B of foundation pipe units adjacent to the group A of foundation pile units coincide. The quasi-large-diameter pile is formed by the plurality of small-diameter piles defining a bunch with a theoretical pile center as the circle center and mutually meshing with each other to form a whole. According to the construction method of the quasi-large-diameter pile, a conventional small-diameter pile construction process is completely adopted, high-power construction machinery investment is not needed, and therefore the advantages of the large-diameter pile are achieved, the construction difficulty is reduced, and the application range is enlarged; multiple pile foundations can be constructed at the same time without the restriction of the large construction machinery, and therefore the construction period of the pile foundations is greatly shortened, the engineering cost is saved, and the economic benefits are obvious.