Recyclable pile foundation

A recyclable pile foundation, comprising:

• at least two inner cylinders coaxially distributed along a first axis thereof, wherein adjacent two inner cylinders of the at least two inner cylinders are detachably connected;
• at least two outer cylinders coaxially distributed along the first axis, wherein each outer cylinder coaxially surrounds a corresponding inner cylinder of the at least two inner cylinders, and each outer cylinder is connected with the corresponding inner cylinder through at least two steel bars;
• and
• at least three reciprocating components circumferentially distributed between the at least two inner cylinders and the at least two outer cylinders, wherein each reciprocating component comprises:
• at least two steel collars, wherein each steel collar is welded to a steel bar of the at least two steel bars;
• a push-pull rod parallel to the first axis, wherein the push-pull rod passes through the at least two steel collars and is only movable along a second axis of the push-pull rod under a limitation of the at least two steel collars;
• a hold component configured to hold the push-pull rod in a pushed position or in a pulled position, wherein the hold component is detachably connected to a head block arranged at an upper end of the push-pull rod;
• and
• at least one motion component distributed along the push-pull rod, wherein each motion component comprises:
• at least one triangular connection plate, wherein each triangular connection plate is fixedly connected to the push-pull rod;
• a plurality of connection rods, wherein each connection rod is fixedly connected to a triangular connection plate of the at least one triangular connection plate;
• an inner wedge block fixedly connected to at least one of the plurality of connection rods, wherein the inner wedge block has a first inclined plane;
• an outer wedge block fixedly connected to at least one of the plurality of connection rods, wherein the outer wedge block has a second inclined plane opposite and parallel to the first inclined plane;
• a motion block arranged between two steel bars of the at least two steel bars, wherein the motion block is only movable perpendicularly to the first axis under a limitation of the two steel bars, the motion block is arranged between the inner wedge block and the outer wedge block and slidably in contact with both the first inclined plane and the second inclined plane;
• and
• a pointed rod perpendicular to the first axis and attached to the motion block;
• wherein:
• when the push-pull rod is pushed along the second axis to the pushed position, the inner wedge block and the outer wedge block move with the push-pull rod to drive the motion block to move, and the pointed rod moves with the motion block and protrudes from an outer cylinder of the at least two outer cylinders passing through a first hole arranged at the outer wedge block and a second hole arranged at the outer cylinder;
• and
• when the push-pull rod is pulled along the second axis to the pulled position, the inner wedge block and the outer wedge block move with the push-pull rod to drive the motion block to move, and the pointed rod moves with the motion block and retracts.