阅读说明：本技术 一种新型变截面灌注桩及其施工方法 (Novel variable cross-section cast-in-place pile and construction method thereof ) 是由 邵先锋 朱克亮 李卫国 陈曦鸣 石雪梅 钱朝军 杨泰朋 宣善钦 刘军 汪和龙 徐 于 2019-09-29 设计创作，主要内容包括：本发明属于灌注桩施工技术领域,具体提供一种新型变截面灌注桩及其施工方法,本发明在灌注桩基坑侧壁的局部扩大基坑孔径形成环形外扩孔,环形外扩孔的位置和数量可根据实际工程情况进行灵活布置,通过外伸装置在环形外扩孔内设置与竖向桩体钢筋笼连接的扩孔钢筋笼,从而浇筑形成具有较高抗压和抗拔承载力的变截面灌注基桩。本发明的变截面灌注桩施工简便,较好地解决了桩的抗压及抗拔承载力不足的问题,具有很强的工程实用性。(The invention belongs to the technical field of cast-in-place pile construction, and particularly provides a novel variable cross-section cast-in-place pile and a construction method thereof. The variable cross-section cast-in-place pile is simple and convenient to construct, well solves the problem that the compressive and uplift bearing capacity of the pile is insufficient, and has strong engineering practicability.)

1. The novel variable cross-section cast-in-place pile is characterized in that the cast-in-place pile is located in a foundation pit and comprises a vertical pile body and a transversely outward-extending reaming reinforcement cage, the outward-extending reaming reinforcement cage is arranged in an annular outer reaming hole, and the foundation pit radially and outwardly extends at an elevation where the outward-extending reaming reinforcement cage is located to form an annular outer reaming hole;

overhanging reaming steel reinforcement cage includes inlayer reaming steel reinforcement cage and outer reaming steel reinforcement cage, the diameter of outer reaming steel reinforcement cage is the same with the diameter of the vertical pile body and sets up in the foundation ditch, outer reaming steel reinforcement cage is connected on the vertical steel reinforcement cage in the vertical pile body, be provided with the guide rail on the outer reaming steel reinforcement cage, inlayer reaming steel reinforcement cage stretches out to the outer reaming of annular along the guide rail in.

2. A novel variable cross-section bored concrete pile according to claim 1, wherein said outer reamed cage includes a guide main rib, a vertical connecting rib, and a transverse connecting rib, said guide main rib being cross-connected to said transverse connecting rib to form a transverse outer mesh reinforcement; the guide main ribs and the vertical connecting ribs are connected in a crossed mode to form vertical outer layer reinforcing mesh, and the two horizontal outer layer reinforcing mesh and the two vertical outer layer reinforcing mesh are enclosed to form a cylindrical outer layer reaming reinforcing cage.

3. A novel variable cross-section bored concrete pile according to claim 2, wherein said outer reamed reinforcement cage is connected to the vertical reinforcement cage by lashing or welding.

4. The novel variable cross-section bored concrete pile as claimed in claim 2, wherein said inner-layer expanded steel reinforcement cage comprises an inner-layer steel reinforcement mesh and a connecting cross bar, a plurality of inner-layer steel reinforcement meshes are arranged at intervals, and a plurality of said inner-layer steel reinforcement meshes are connected together through the connecting cross bar to form the inner-layer expanded steel reinforcement cage;

the inner-layer reinforcing mesh comprises guide transverse ribs and connecting vertical ribs, the guide transverse ribs and the connecting vertical ribs are connected in a cross mode to form a latticed inner-layer reinforcing mesh, the guide transverse ribs on the top of the inner-layer reinforcing mesh and the guide transverse ribs on the bottom of the inner-layer reinforcing mesh are arranged in parallel, and the connecting vertical ribs are arranged between the guide transverse ribs on the top and the guide transverse ribs on the bottom of the inner-layer reinforcing mesh;

the guide transverse ribs at the top and the bottom of the inner-layer reaming reinforcement cage are arranged in the guide rail;

preferably, the guide rail is a guide rail with a rectangular groove.

5. The novel variable cross-section bored concrete pile according to claim 2, wherein the outer reamed reinforcement cage is a rectangular parallelepiped frame structure, and two of the inner reamed reinforcement cages are respectively disposed at both ends of the outer reamed reinforcement cage and extend from the inside of the outer reamed reinforcement cage into the annular outer reamed hole; preferably, outer reaming steel reinforcement cage is provided with two, two outer reaming steel reinforcement cage cross arrangement, two outer reaming steel reinforcement cage all follows the radial setting of vertical pile body.

6. The novel variable cross-section cast-in-place pile as claimed in claim 4, wherein the transverse outer steel bar mesh is of a fan-ring structure, two adjacent inner steel bar meshes are connected by a plurality of connecting transverse bars, each connecting transverse bar is of a telescopic structure, each connecting transverse bar comprises an A sliding bar, a B sliding bar and a sliding sleeve, fixed ends of the A sliding bar and the B sliding bar are respectively connected with the inner steel bar mesh, free ends of the A sliding bar and the B sliding bar penetrate into the sliding sleeve from two ends of the sliding sleeve, and the A sliding bar and the B sliding bar slide freely along the sliding sleeve to realize extension and shortening of the connecting transverse bars;

preferably, the connecting transverse bar is arranged at the joint of the guide transverse bar and the connecting vertical bar in two adjacent inner steel bar nets.

7. A novel variable cross-section bored concrete pile according to claim 6, wherein said inner reamed cage extends to said annular outer reamed area and partially overlaps said outer reamed cage.

8. A novel variable cross-section bored concrete pile according to any one of claims 1 to 6, wherein the overhanging reaming steel reinforcement cage further includes steel reinforcement cage displacement pull rod, steel reinforcement cage displacement pull rod includes mobile jib and auxiliary rod, the mobile jib sets up in the steel reinforcement cage displacement pull rod protects intraductally and follows steel reinforcement cage displacement pull rod protects the pipe and freely slides, the both ends of mobile jib stretch out steel reinforcement cage displacement pull rod protects the pipe, the bottom of mobile jib is located the outer reaming elevation department of annular, the one end of auxiliary rod with the bottom of mobile jib is articulated, the other end with inlayer reaming steel reinforcement cage is articulated.

9. The construction method of the novel variable cross-section cast-in-place pile as claimed in any one of claims 1 to 8, wherein the construction method comprises the following steps:

step S1, drilling an annular outer reaming hole, and reaming at the connection elevation of the outer layer reaming reinforcement cage and the vertical reinforcement cage to form the annular outer reaming hole;

step S2, lowering the vertical reinforcement cage in the vertical pile body into the foundation pit, and extending the outward-extending reaming reinforcement cage into the annular outer reaming hole in the step S1;

and step S3, integrally pouring the vertical reinforcement cage in the vertical pile body of the variable cross-section cast-in-place pile and the outward-extending reaming reinforcement cage to obtain the variable cross-section cast-in-place pile.

Technical Field

The invention belongs to the technical field of cast-in-place pile construction, and particularly relates to a novel variable cross-section cast-in-place pile and a construction method thereof.

Background

The compression resistance and the pulling resistance of the common cast-in-place pile are general, and compared with the cast-in-place pile with the same cross section, the bearing capacity of the cast-in-place pile with the variable cross section is greatly improved, and the settlement is reduced. However, the existing variable cross-section cast-in-place pile is difficult to construct in detail and the construction cost is high.

Aiming at the series of defects, the variable cross-section cast-in-place pile can be arranged at different positions of the pile body according to different bearing capacities required by the pile foundation, the size, the position and the number of the variable cross-sections can be flexibly arranged, the device is simple and easy to implement, the manufacturing process is simple, the processing and binding are easy, the manufacturing cost is low, the implementation is convenient, the universality is strong, the defects of the equal cross-section pile and the conventional variable cross-section pile are overcome, and the variable cross-section cast-in-place pile has a good application prospect.

Disclosure of Invention

The invention aims to provide a novel variable cross-section cast-in-place pile and a construction method thereof, which at least solve the problems that the compressive and tensile bearing capacity of the conventional constant cross-section pile is weakened when in use, the conventional variable cross-section pile is difficult to construct, the cost is high and the like.

In order to achieve the above purpose, the invention provides the following technical scheme:

a novel variable cross-section bored concrete pile is located in a foundation pit and comprises a vertical pile body and a transverse outward-extending reaming reinforcement cage, wherein the outward-extending reaming reinforcement cage is arranged in an annular outer reaming hole, and the foundation pit radially and outwardly extends at an elevation where the outward-extending reaming reinforcement cage is located to form an annular outer reaming hole;

overhanging reaming steel reinforcement cage includes inlayer reaming steel reinforcement cage and outer reaming steel reinforcement cage, the diameter of outer reaming steel reinforcement cage is the same with the diameter of the vertical pile body and sets up in the foundation ditch, outer reaming steel reinforcement cage is connected on the vertical steel reinforcement cage in the vertical pile body, be provided with the guide rail on the outer reaming steel reinforcement cage, inlayer reaming steel reinforcement cage stretches out to the outer reaming of annular along the guide rail in.

According to the novel variable cross-section cast-in-place pile, preferably, the outer-layer reaming reinforcement cage comprises a guide main rib, a vertical connecting rib and a transverse connecting rib, and the guide main rib and the transverse connecting rib are connected in a cross manner to form a transverse outer-layer reinforcement mesh; the guide main ribs and the vertical connecting ribs are connected in a cross mode to form vertical outer layer reinforcing mesh, and the two transverse outer layer reinforcing mesh and the two vertical outer layer reinforcing mesh are enclosed to form a cylindrical outer layer reaming reinforcing cage.

According to the novel variable cross-section cast-in-place pile, preferably, the outer reaming reinforcement cage is connected to the vertical reinforcement cage through binding or welding.

According to the novel variable cross-section cast-in-place pile, preferably, the inner-layer reaming reinforcement cage comprises inner-layer reinforcement meshes and connecting transverse bars, a plurality of inner-layer reinforcement meshes are arranged at intervals, and the inner-layer reinforcement meshes are connected together through the connecting transverse bars to form the inner-layer reaming reinforcement cage;

the inner-layer reinforcing mesh comprises guide transverse ribs and connecting vertical ribs, the guide transverse ribs and the connecting vertical ribs are connected in a cross mode to form a latticed inner-layer reinforcing mesh, the guide transverse ribs on the top of the inner-layer reinforcing mesh and the guide transverse ribs on the bottom of the inner-layer reinforcing mesh are arranged in parallel, and the connecting vertical ribs are arranged between the guide transverse ribs on the top and the guide transverse ribs on the bottom of the inner-layer reinforcing mesh;

the guide transverse ribs at the top and the bottom of the inner-layer reaming reinforcement cage are arranged in the guide rail;

still preferably, the guide rail is a guide rail with a rectangular groove.

According to the novel variable cross-section cast-in-place pile, preferably, the outer-layer reaming reinforcement cage is of a rectangular frame structure, the two inner-layer reaming reinforcement cages are respectively arranged at two ends of the outer-layer reaming reinforcement cage, and the inner-layer reaming reinforcement cage extends into the annular outer reaming hole from the inside of the outer-layer reaming reinforcement cage; preferably, outer reaming steel reinforcement cage is provided with two, two outer reaming steel reinforcement cage cross arrangement, two outer reaming steel reinforcement cage all follows the radial setting of vertical pile body.

According to the novel variable cross-section cast-in-place pile, preferably, the transverse outer-layer steel bar mesh is of a fan-shaped annular structure, two adjacent inner-layer steel bar meshes are connected through a plurality of connecting transverse bars, each connecting transverse bar is of a telescopic structure and comprises an a sliding bar, a B sliding bar and a sliding sleeve, fixed ends of the a sliding bar and the B sliding bar are respectively connected with the inner-layer steel bar mesh, free ends of the a sliding bar and the B sliding bar penetrate into the sliding sleeve from two ends of the sliding sleeve respectively, and the a sliding bar and the B sliding bar freely slide along the sliding sleeve, so that the connecting transverse bars are extended and shortened;

still preferably, the connecting transverse bar is arranged at the joint of the guiding transverse bar and the connecting vertical bar in two adjacent inner steel bar nets.

In the novel variable cross-section cast-in-place pile, preferably, the inner-layer reamed reinforcement cage extends to the annular outer reamed hole and then partially overlaps with the outer-layer reamed reinforcement cage.

As above novel variable cross-section bored concrete pile, preferably, overhanging reaming steel reinforcement cage still includes steel reinforcement cage displacement pull rod, steel reinforcement cage displacement pull rod includes mobile jib and auxiliary rod, the mobile jib sets up in steel reinforcement cage displacement pull rod protects intraductally and follows steel reinforcement cage displacement pull rod protects the pipe free slip, stretch out at the both ends of mobile jib steel reinforcement cage displacement pull rod protects the pipe, the bottom of mobile jib is located outer reaming elevation place of annular, the one end of auxiliary rod with the bottom of mobile jib is articulated, the other end with inlayer reaming steel reinforcement cage is articulated.

The construction method of the novel variable cross-section cast-in-place pile preferably comprises the following steps:

step S1, drilling an annular outer reaming hole, and reaming at the connecting elevation of the outer layer reaming reinforcement cage and the vertical reinforcement cage to form the annular outer reaming hole;

step S2, lowering the vertical reinforcement cage in the vertical pile body into the foundation pit, and extending the outward-extending reaming reinforcement cage into the annular outer reaming hole in the step S1;

and step S3, integrally pouring the vertical reinforcement cage in the vertical pile body of the variable cross-section cast-in-place pile and the outward-extending reaming reinforcement cage to obtain the variable cross-section cast-in-place pile.

Compared with the closest prior art, the technical scheme provided by the invention has the following excellent effects:

the invention provides a novel variable cross-section bored concrete pile and a construction method thereof.A hole diameter of the side wall of a foundation pit at an elevation where an outward-extending reaming reinforcement cage is located is enlarged to form an annular outward-extending reaming, the reaming reinforcement cage is bound or welded with a constant-diameter reinforcement cage of a vertical pile body of the variable cross-section bored concrete pile, the connection positions and the number are flexibly arranged according to the actual engineering situation, the outward-extending reaming reinforcement cage comprises an outer-layer reaming reinforcement cage and an inner-layer reaming reinforcement cage, and the inner-layer reaming reinforcement cage slides relative to the outer-layer reaming reinforcement cage and extends into the annular. The steel reinforcement cage displacement pull rod is connected with the inner-layer reaming steel reinforcement cage, so that the sliding of the inner-layer steel reinforcement cage is remotely controlled (the inner-layer steel reinforcement cage in the deep pile hole is controlled from the ground), the steel reinforcement cage displacement pull rod is simple in structure, and the cost is low. After concrete pouring is finished, the overhanging reaming reinforcement cage and the concrete of the equal-diameter reinforcement cage of the vertical pile body of the variable cross-section cast-in-place pile are connected into a whole, so that the compressive and tensile bearing capacity of the foundation pile is greatly enhanced. The outer-layer reaming steel reinforcement cage and the inner-layer reaming steel reinforcement cage are adopted as the outer-layer reaming steel reinforcement cage, the device is simple and easy to operate, easy to process and bind, simple in overall structure and low in construction cost. The outer-layer reaming reinforcement cage and the vertical pile body equal-diameter reinforcement cage of the variable-section cast-in-place pile are bound or welded together, so that a pile hole where the vertical pile body equal-diameter reinforcement cage of the variable-section cast-in-place pile is located and an annular outer-reaming structure are cast into a whole, the resistance to pressure and pulling of a common equal-section pile is obviously improved, the bearing capacity of the cast-in-place pile is improved, compared with the conventional variable-section pile, the variable-section positions, the variable-section number and the variable-section size of the pile can be flexibly set according to the actual engineering situation, the construction is simple and easy, the defects of the common equal-section pile are overcome, the application level of the conventional variable-section pile is also obviously improved, and therefore, the variable-section cast.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate exemplary embodiments of the invention and, together with the description, serve to explain the invention and are not intended to limit the invention.

Wherein:

fig. 1 is a schematic structural view of a cast-in-place pile in which an annular outer counterbore is located at the upper part of a pile body and an inner-layer counterbore reinforcement cage does not extend to the annular outer counterbore according to an embodiment of the present invention;

fig. 2 is a schematic structural view of a cast-in-place pile after an annular outer counterbore is positioned at the upper part of a pile body and an inner-layer counterbore reinforcement cage extends out to the annular outer counterbore according to the embodiment of the invention;

fig. 3 is a schematic structural view of a cast-in-place pile with an annular outer counterbore at the bottom of the pile body and an inner-layer counterbore reinforcement cage not extending out to the annular outer counterbore according to the embodiment of the invention;

fig. 4 is a schematic structural view of a cast-in-place pile after an annular outer counterbore is located at the bottom of a pile body and an inner-layer counterbore reinforcement cage extends out to the annular outer counterbore according to the embodiment of the invention;

FIG. 5 is a view from A to A of FIG. 1 in embodiment 1 of the present invention;

FIG. 6 is a view A-A of FIG. 2 in the embodiment 1 of the present invention;

FIG. 7 is a view from A to A of FIG. 1 in embodiment 2 of the present invention;

FIG. 8 is a view from A-A of FIG. 2 in accordance with embodiment 2 of the present invention;

fig. 9 is a schematic structural view of the inner-layer reamed reinforcement cage in an unextended state according to the embodiment of the present invention;

fig. 10 is a schematic structural view of the inner-layer reamed steel reinforcement cage in an extended state according to the embodiment of the invention;

FIG. 11 is a schematic view of the positional relationship between the outer and inner reamed cages of FIG. 6

FIG. 12 is a schematic view of a rail structure according to an embodiment of the present invention;

fig. 13 is a schematic structural view of an inner-layer reamed reinforcement cage in embodiment 2 of the present invention in a non-extended state;

fig. 14 is a schematic structural view of the inner-layer reamed steel reinforcement cage in the extended state in embodiment 2 of the present invention.

In the figure: 1. a vertical reinforcement cage; 4. extending the hole enlarging reinforcement cage; 16. a steel reinforcement cage displacement pull rod; 17. a steel reinforcement cage displacement pull rod protective pipe; 21. ring-shaped outer reaming; 22. a guide rail; 23. reaming a steel reinforcement cage on the outer layer; 24. Inner-layer reaming reinforcement cages; 25. concrete grouting pipes; 26. a grouting system; 27. vertical connecting ribs; 28. A sliding sleeve; 29. guiding the main ribs; 30. transverse connecting ribs; 31. connecting the transverse ribs; 32. a guide transverse rib; 33. connecting vertical ribs; 34. a main rod; 35. and an auxiliary rod.

Detailed Description

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

In the description of the present invention, the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", etc., indicate orientations or positional relationships based on those shown in the drawings, and are for convenience of description only and do not require that the present invention be constructed and operated in a particular orientation, and thus should not be construed as limiting the present invention. The terms "connected" and "connected" used herein should be interpreted broadly, and may include, for example, a fixed connection or a detachable connection; they may be directly connected or indirectly connected through intermediate members, and specific meanings of the above terms will be understood by those skilled in the art according to specific situations.