CN-120739113-B - Construction method of prefabricated hollow stiff pile with extension wings

CN120739113BCN 120739113 BCN120739113 BCN 120739113BCN-120739113-B

Abstract

The invention provides a construction method of a prefabricated hollow stiff pile with extension wings, which belongs to the field of construction of prefabricated hollow stiff piles and comprises a stiff pile body, a hammering limiting device, an impact bullet, a plurality of extension wings circularly arrayed along the central line of the stiff pile body, wherein during construction, holes are formed in the ground, slurry is injected into the holes, the impact bullet is filled up to the hollow bottom of the stiff pile body from the bottom end of the stiff pile body, then the extension wings are temporarily fixed to an undeployed state, the stiff pile body with the temporarily fixed extension wings is placed in the holes, the slurry wraps the stiff pile body outside, and then the impact bullet at the bottom of the stiff pile body is repeatedly hammered by using the hammering limiting device, so that the impact bullet pushes the extension wings at the bottom of the stiff pile body to be unfolded towards the outer wall of the stiff pile body, and bottom expansion is realized.

Inventors

QIAN KUN
ZOU WUSONG
CHEN XIONG
QIAN YONG
WU LAIWEN
Wu haian

Assignees

联保(江西)工程技术有限公司
江西天康建设工程有限公司

Dates

Publication Date: 20260505
Application Date: 20250822

Claims (8)

1. The construction method of the prefabricated hollow stiff pile with the extension wings is characterized by comprising the following steps of: A pore-forming step of forming pores on the ground and injecting slurry into the pores; filling the impact bullet from the bottom end of the prefabricated hollow stiff pile to the hollow bottom of the prefabricated hollow stiff pile, closing the bottom end of the prefabricated hollow stiff pile by a bottom expanding unit, placing the prefabricated hollow stiff pile in a hole after closing, wrapping the prefabricated hollow stiff pile outside by slurry, and drying the hollow interior of the prefabricated hollow stiff pile; Repeatedly hammering the impact bullet at the bottom of the prefabricated hollow stiff pile by using a hammering limiting device, so that the impact bullet pushes the extension wings at the bottom of the prefabricated hollow stiff pile to extend towards the outer wall of the prefabricated hollow stiff pile; In the pile-down step, the prefabricated hollow stiff pile comprises: the upper end face and the lower end face of the stiff pile body penetrate through first through holes; The bottom expanding unit is arranged at the bottom of the stiff pile body and comprises a plurality of extending wings, the extending wings are circularly arrayed along the central line of the stiff pile body, the extending wings are triangular prisms, each extending wing is hinged with the lower end face of the stiff pile body, and the rotating axis of the hinged position of each extending wing is perpendicular to the central line of the stiff pile body; When the extending wings are not unfolded, the extending wings close the lower end surfaces of the first through holes; In the process that the extending wings rotate to the unfolding state, the lower end face of the first through hole is opened by the extending wings, and the extending wings form a bottom expanding at the bottom end of the stiff pile body; In the bottom expanding step, the hammering limiting device comprises a mounting block, a spring, a sliding block, an inner hammer, a connecting rope and a hammer lifting block; The mounting block is fixedly mounted on the upper end face of the stiff pile body, the upper end face and the lower end face of the mounting block penetrate through second through holes, the cross section of the second through holes is the same as the cross section of the first through holes, and the second through holes are communicated with the first through holes; The mounting block is provided with a plurality of springs in a circular array along the central line of the stiff pile body, the lower end faces of the springs are fixedly connected with the upper end face of the mounting block, the lower end face of the sliding block is provided with a groove, the upper end faces of the springs are fixedly connected with the upper end face of the groove, the mounting block is positioned in the groove, and the sliding direction of the sliding block is consistent with the extending direction of the springs; The upper end surface and the lower end surface of the sliding block are penetrated with a third through hole, the cross section of the third through hole is the same as the cross section of the second through hole, and the third through hole is communicated with the second through hole; One end of the connecting rope is fixedly connected with the upper end face of the inner hammer, the other end of the connecting rope is fixedly connected with the lower end face of the lifting hammer block, and when the inner hammer strikes the impact bullet in the stiff pile body, the lifting hammer block contacts and presses the upper end face of the sliding block.
2. The method for constructing a prefabricated hollow stiff pile with extension wings according to claim 1, wherein the extension wings comprise a first side wall, a second side wall and a third side wall; When the extending wings are not unfolded, the third side wall on the extending wings is flush with the corresponding outer side wall of the stiffening pile body, the first side wall on one extending wing is attached to the second side wall on the extending wing adjacent to the other extending wing, and the second side wall on one extending wing is attached to the first side wall on the extending wing adjacent to the other extending wing.
3. The construction method of the prefabricated hollow stiff pile with the extension wing according to claim 2, wherein the reinforcing steel bars are embedded at the junction of the first side wall and the second side wall on the extension wing, the upper end faces of the reinforcing steel bars are flush with the upper end faces of the extension wing, and the lower end faces of the reinforcing steel bars extend out of the lower end faces of the extension wing.
4. The method for constructing prefabricated hollow stiff piles with extension wings according to claim 3, wherein the rotation axis of the hinge of each extension wing is equal to the upper end face of each extension wing when the extension wings are not unfolded.
5. The method of claim 1, wherein in the bottom expanding step, the side wall of the impact bullet and the inner side wall of the stiff pile body are sealed by a sealing ring, the head of the impact bullet is conical, and the head of the impact bullet is positioned at the lower end of the impact bullet.
6. The method of constructing a prefabricated hollow stiff pile with extension wings as set forth in claim 1, wherein the cross section of the inner hammer is smaller than the cross section of the first through hole.
7. The method of constructing a prefabricated hollow stiff pile with extension wings as set forth in claim 1, wherein the outer side wall of the lifting block is flush with the outer side wall of the sliding block when the lifting block is pressed in contact with the sliding block.
8. The method for constructing a prefabricated hollow stiff pile with extension wings according to claim 1, wherein when the extension wings are hammered to an extended state by the inner hammer, the upper end face of the groove is attached to the upper end face of the installation block, the lower end face of the sliding block is flush with the lower end face of the installation block, the distance from the upper end face of the impact bullet head to the upper end face of the sliding block is a, the length of the connecting rope is b, the height of the inner hammer is c, and a=b+c.

Description

Construction method of prefabricated hollow stiff pile with extension wings Technical Field The invention belongs to the field of construction of prefabricated hollow stiff piles, and particularly relates to a construction method of a prefabricated hollow stiff pile with extension wings. Background Pile foundations are widely applied in civil engineering and are used for transmitting superstructure loads to soil layers or rock layers with good deep bearing capacity, and among a plurality of piles, prefabricated hollow piles (such as prestressed concrete piles, PHC piles and hollow square piles) are applied in large scale in industrial and civil construction, bridges, wharfs and other engineering due to the remarkable advantages of stable industrial production quality, high construction speed, no slurry pollution, relative economy of construction cost and the like. In order to remarkably improve the end bearing force of a single pile, reduce sedimentation and fully utilize the bearing force of a deep bearing layer, a pedestal pile technology is often adopted in engineering practice, and the pedestal pile is formed into a multiplied pile-soil contact area by forming an enlarged head with the diameter larger than that of a pile body at the pile end, so that the pile end resistance is greatly improved (can be improved by 50 percent or even higher than that of a straight pile with the same diameter). However, existing under-reamed piles are usually under-reamed by a mechanical reamer, in particular, by using a special reamer (such as a hydraulic reamer, a mechanical link type reamer, etc.) installed at the bottom of a drill rod, and under the driving of a drilling machine, an enlarged cavity is formed at the bottom of a hole by a bottom-reamed mechanism of the drill, but this way, the complex and heavy bottom-reamed mechanism is integrated into a precast pile or sunk with the pile, which greatly increases the structural complexity and manufacturing cost of the pile body and even affects the structural integrity of the pile body. Disclosure of Invention In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a construction method of a prefabricated hollow stiff pile with extension wings, which is used for solving the problems that the bottom expanding mechanism in the prior art increases the complexity of the pile body structure and the manufacturing cost. To achieve the above and other related objects, the present invention provides a method of constructing a prefabricated hollow stiff pile with extension wings, the method comprising: A pore-forming step of forming pores on the ground and injecting slurry into the pores; placing the prefabricated hollow stiff pile in the hole, and wrapping the prefabricated hollow stiff pile outside by the slurry, wherein the hollow part of the prefabricated hollow stiff pile is still dry; And (3) a bottom expanding step, namely repeatedly hammering the impact bullet at the bottom of the prefabricated hollow stiff pile by using a hammering limiting device, so that the impact bullet pushes the extension wings at the bottom of the prefabricated hollow stiff pile to be unfolded towards the outer wall of the prefabricated hollow stiff pile. Alternatively, in the pile-down step, the prefabricated hollow stiff pile includes: the upper end face and the lower end face of the stiff pile body penetrate through first through holes; The bottom expanding unit is arranged at the bottom of the stiff pile body and comprises a plurality of extending wings, the extending wings are circularly arrayed along the central line of the stiff pile body, the extending wings are triangular prisms, each extending wing is hinged with the lower end face of the stiff pile body, and the rotating axis of the hinged position of each extending wing is perpendicular to the central line of the stiff pile body; When the extending wings are not unfolded, the extending wings close the lower end surfaces of the first through holes; in the process that the extending wings rotate to the unfolding state, the lower end face of the first through hole is opened by the extending wings, and the extending wings form a bottom expanding at the bottom end of the stiff pile body. Alternatively, the side wall of the stretching wing comprises a first side wall, a second side wall and a third side wall; When the extending wings are not unfolded, the third side wall on the extending wings is flush with the corresponding outer side wall of the stiffening pile body, the first side wall on one extending wing is attached to the second side wall on the extending wing adjacent to the other extending wing, and the second side wall on one extending wing is attached to the first side wall on the extending wing adjacent to the other extending wing. As an alternative scheme, the junction of the first side wall and the second side wall on the extending wing is embedded with a reinforcing steel bar