CN202031083U

CN202031083U - Prestress hollow square pile

Info

Publication number: CN202031083U
Application number: CN 201120114900
Authority: CN
Inventors: 张强; 朱建舟
Original assignee: Shanghai Zhongji Pile Industry Co Ltd
Current assignee: Bao Lei
Priority date: 2011-04-19
Filing date: 2011-04-19
Publication date: 2011-11-09
Anticipated expiration: 2021-04-19

Abstract

A prestress hollow square pile comprises a reinforcement cage and concrete. The reinforcement cage comprises framework main steel bars and stirrups. The stirrups are continuously welded on the framework main steel bars in a spiral shape. Two ends of the prestress hollow square pile are provided with metal end plates connected with the reinforcement cage, hoops are arranged at the joint portions of the metal end plates and a pile body, the prestress hollow square pile is in a square shape, and a pile core is a cylindrical central hole. Quadrilateral corners of the prestress hollow square pile are in a circular shape which can eliminate stress, an arc radius R1 of a pair of arc angles on a diagonal is larger than an arc radius R2 of the other pair of arc angles, and the reinforcement cage further comprises at least two auxiliary ribs which are parallel to the framework main steel bars and connected to the stirrups in welding mode. The prestress hollow square pile is not easy to be damaged, has the pile body with good ductility, and has good bending-resistance and shear-resistance.

Description

Hollow square prestressed pile

Technical Field

The utility model relates to a hollow square pile of prestressing force.

Background

The prestressed square pile is willing to be adopted in the building industry due to the advantages of superior strength, high rigidity, bending resistance, strong crack resistance and the like of the prestressed square pile compared with the common square pile. However, due to the structural defects of the pile cage, all the main reinforcements cannot be tightly combined effectively, so that the connectivity of the pile cage is reduced, and the quality of the pile section is influenced. In addition, when in actual use, the required length can be achieved through effective connection between pile sections, the existing prestressed square pile is only connected through welding between angle irons connected with stirrups, and as the 'main reinforcement connection' cannot be realized and only the 'vertical welding' can be realized during welding, the welding quality is difficult to guarantee, so that the bending resistance of the whole pile formed by welding each pile section is poor.

A pretensioning method prestressed concrete hollow square pile product is also used in the building foundation engineering, and the pretensioning method prestressed concrete hollow square pile product is divided into two types according to the concrete strength and the inner diameter of the hollow square pile: prestressed concrete hollow square piles (PS piles for short) and prestressed concrete hollow square piles (PHS piles for short). Longitudinal steel bars configured for the two hollow square pile products are prestressed steel bars, the two types of prestressed concrete upper hollow square piles have good crack resistance, but are easy to brittle fracture when meeting hard objects in transportation and construction or excavating pile foundations after construction, the hollow square piles have large brittleness, small deformation, poor bending toughness and weak shear resistance when being stressed, and the hollow square piles are easy to damage particularly when being subjected to horizontal load action such as earthquake load.

SUMMERY OF THE UTILITY MODEL

The utility model provides a hollow square pile of prestressing force to reduce or avoid the aforementioned problem.

In order to solve the problems, the utility model provides a prestressed hollow square pile, which comprises a reinforcement cage and concrete; the reinforcement cage comprises a framework main reinforcement and a stirrup, and the stirrup is spirally and continuously welded on the framework main reinforcement; the two ends of the prestressed hollow square pile are provided with metal end plates connected with the reinforcement cage, a hoop is arranged at the connecting part of the metal end plates and the pile body, the prestressed hollow square pile is square in shape, and the pile core is a cylindrical middle hole; the four sides corner of hollow square pile of prestressing force is stress relief arc, and wherein the circular arc radius R1 of a pair of circular arc angle on the diagonal is greater than the circular arc radius R2 of another pair of circular arc angle, the steel reinforcement cage still include at least two with the parallel, with stirrup welded connection's auxiliary reinforcement of skeleton owner muscle.

Preferably, the shape of the metal end plate is the same as the shape of the pile body of the prestressed hollow square pile, welding grooves are formed in four sides of the metal end plate, the center of the metal end plate is a round hole with the same diameter as the middle hole of the prestressed hollow square pile, and threading holes and tension holes are symmetrically formed between the round hole and the four sides of the metal end plate.

Preferably, the tension hole is connected with the threading hole through a rib groove.

Preferably, the threading holes and the tension holes in the metal end plate are in a square layout, and the threading holes are counter-sunk holes.

Preferably, the main frame rib is a steel bar, the main frame rib is parallel to the contour line of the pile body, and a connecting part of the steel bar and the metal end plate is provided with a heading.

The utility model provides a hollow square pile of prestressing force owing to adopted hollow shape, consequently economizes material, dead weight is light, and pile body four sides corner is stress relief arc, and the pile head is connected with the cuff for the stake material is not fragile when the construction hammering, has improved the product and has become the stake rate.

The utility model provides a hollow square pile of prestressing force, main muscle is rationally distributed, the stirrup is the heliciform welding on the main muscle to have the auxiliary reinforcement parallel with the main muscle, so pile body ductility is good, it is big to become the stake bearing capacity, and bending resistance shear behavior is good.

The utility model provides a hollow square pile of prestressing force, end plate have the welding groove and have also strengthened the fastness of becoming the stake and connecting.

Drawings

The drawings are only intended to illustrate and explain the present invention and do not limit the scope of the invention. Wherein,

fig. 1 is a schematic structural view of a prestressed hollow square pile according to an embodiment of the present invention;

fig. 2 is a schematic view of a partially cut-away structure of a prestressed hollow square pile according to an embodiment of the present invention;

fig. 3 is a top view of a prestressed hollow square pile according to an embodiment of the present invention;

FIG. 4 is a schematic cross-sectional view of the pre-stressed hollow square pile shown in FIG. 1;

FIG. 5 is a schematic cross-sectional view A-A of the pre-stressed hollow square pile shown in FIG. 3;

fig. 6 is an enlarged view of the portion C of the prestressed hollow square pile shown in fig. 3.

Detailed Description

In order to clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will be described with reference to the accompanying drawings. Wherein like parts are given like reference numerals.

The structure and the principle of the prestressed hollow square pile according to the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 is a schematic structural view of an external appearance of a prestressed hollow square pile according to an embodiment of the present invention; fig. 4 is a schematic cross-sectional view of the prestressed hollow square pile shown in fig. 1. For the sake of clarity, the three-axis vertical coordinate system is used as a reference in the drawing, wherein the direction along the coordinate axis z is the axial direction of the prestressed hollow square pile, the direction along the coordinate axis x is the transverse direction of the section of the prestressed hollow square pile, and the direction along the coordinate axis y is the longitudinal direction of the section of the prestressed hollow square pile.

Specifically, referring to fig. 1 and 4, the prestressed hollow square pile comprises a reinforcement cage 1 and concrete 2. The reinforcement cage 1 comprises a framework main reinforcement 11 and stirrups 12, and the stirrups 12 of the reinforcement cage are spirally and continuously welded on the framework main reinforcement 11; the prestressed hollow square pile is square in shape, the pile core is a cylindrical middle hole, corners on four sides of the prestressed hollow square pile are in a stress relief arc shape, wherein the arc radius R1 of a pair of arc angles on a diagonal line is 30-40mm, and the arc angle is 90 degrees; the arc radius R2 of the other pair of arc angles is 10-20mm, and the arc angles are also 90 degrees. That is, the prestressed hollow square pile has one pair of stress relief arc corners having a larger arc radius R1 and the other pair of stress relief arc corners having a smaller arc radius R2, that is, one pair of arc corners on the diagonal has a larger arc radius R1 than the other pair of arc corners has an arc radius R2.

The corners of four sides of the pile body are arc-shaped for eliminating stress, so that the pile material is not easy to damage when being hammered in building construction. The two ends of the prestressed hollow square pile are provided with metal end plates 3 connected with the reinforcement cage 1, so that the strength of the pile head is further enhanced. The reinforcement cage 1 further comprises at least two auxiliary reinforcements 13 which are parallel to the framework main reinforcement 11 and are connected with the stirrups 12 in a welding mode, and the bending resistance and the shearing resistance of the pile body are further enhanced.

The utility model discloses in, the auxiliary reinforcement 13 is on a parallel with skeleton owner muscle 11 and arranges, and its difference with skeleton owner muscle 11 lies in, and the both ends of skeleton owner muscle 11 are connected respectively on the metal end plate 3 at hollow square pile both ends of prestressing force for undertake along axial pulling force of pile body or pressure. And the two ends of the auxiliary reinforcement 13 or at least one end is not connected on the metal end plate 3 for bearing the horizontal shearing force of the pile body, the prestressed hollow square pile in the prior art is not provided with the auxiliary reinforcement, and the bending resistance and the shearing resistance are slightly poor compared with the technical scheme of the utility model.

In another embodiment, the auxiliary reinforcement 13 is a non-prestressed reinforcement, and is uniformly distributed on the stirrups 12 on at least two symmetrical sides of the pile body section.

Fig. 2 is a schematic view of a partial cross-sectional structure of a prestressed hollow square pile according to the present invention, as shown in the figure, the shape of the metal end plate 3 is the same as the shape of the pile body, and the four sides of the two end plates are provided with welding grooves 32, so as to enhance the firmness of pile-forming connection.

In another embodiment, the main frame rib 11 is parallel to the pile body contour line.

Fig. 3 is a top view of a prestressed hollow square pile according to an embodiment of the present invention; FIG. 5 is a schematic cross-sectional view A-A of the pre-stressed hollow square pile shown in FIG. 3; fig. 6 is an enlarged view of the portion C of the prestressed hollow square pile shown in fig. 3. Referring to fig. 3, 5 and 6, the center of the metal end plate 3 is a circular hole with the same diameter as the hole in the pile core, a threading hole 311 and tension holes 313 are symmetrically arranged between the circular hole and four sides, and each tension hole 313 is connected with the threading hole 311 through a rib groove 312.

In another embodiment, the main frame rib 11 is a steel rod, and the joint of the steel rod and the metal end plate 3 is provided with a heading, so that the connection between the steel rod and the end plate 3 can be more stable.

In another embodiment, the threading holes 311 and the tension holes 313 on the metal end plate 3 are arranged in a generally square shape, and the threading holes 311 are countersunk holes, so that damage to the upset heads of the framework main bars 11 during hammering in construction can be avoided.

In another embodiment, the ferrule 4 is arranged at the connection part of the metal end plate 3 and the pile body, so that the strength of the pile head can be further enhanced, and the pile head is prevented from being damaged when hammering in construction.

In another embodiment, the length L of the cuff 4 is 110mm to 320 mm. The hoop 4 is provided with 2-4 bulges with the radius of 1-3mm at equal intervals along the axial direction of the concrete hollow square pile.

It is to be understood by those skilled in the art that while the present invention has been described in terms of several embodiments, it is not intended that each embodiment cover a separate embodiment. The description is given for clearness of understanding only, and it is to be understood that all matters in the embodiments are to be interpreted as including all technical equivalents which are encompassed by the claims.

The above description is only exemplary of the present invention, and is not intended to limit the scope of the present invention. Any equivalent changes, modifications and combinations that may be made by those skilled in the art without departing from the spirit and principles of the invention should be considered within the scope of the invention.

Claims

1. A prestressed hollow square pile comprises a reinforcement cage (1) and concrete (2); the reinforcement cage (1) is characterized by comprising a framework main reinforcement (11) and stirrups (12), wherein the stirrups (12) are spirally and continuously welded on the framework main reinforcement (11); the two ends of the prestressed hollow square pile are provided with metal end plates (3) connected with the reinforcement cage (1), a hoop (4) is arranged at the connection part of the metal end plates (3) and the pile body, the prestressed hollow square pile is square in appearance, and the pile core is a cylindrical middle hole; the four sides corner of hollow square pile of prestressing force is stress relief arc, and wherein the circular arc radius R1 of a pair of circular arc angle on the diagonal is greater than the circular arc radius R2 of another pair of circular arc angle, steel reinforcement cage (1) still include at least two with skeleton owner muscle (11) parallel, with stirrup (12) welded connection's auxiliary reinforcement (13).

2. The prestressed hollow square pile according to claim 1, wherein the shape of the metal end plate (3) is the same as the shape of the pile body of the prestressed hollow square pile, four sides of the metal end plate (3) are provided with welding bevels (32), the center of the metal end plate is a round hole with the same diameter as the middle hole of the prestressed hollow square pile, and a threading hole (311) and a tension hole (313) are symmetrically arranged between the round hole and the four sides of the metal end plate (3).

3. The prestressed hollow square pile according to claim 2, wherein said tension hole (313) is connected to said threading hole (311) by a rib groove (312).

4. The prestressed hollow square pile according to claim 3, wherein said threading holes (311) and said tension holes (313) of said metal end plate (3) are in a square arrangement, said threading holes (311) being counter-sunk holes.

5. The prestressed hollow square pile according to claim 4, wherein the main frame ribs (11) are steel bars, the main frame ribs (11) are parallel to the contour line of the pile body, and the joints of the steel bars and the metal end plates (3) are provided with upset heads.