CN115748674B - Leakage-proof anti-pulling pile - Google Patents

Abstract

The invention relates to a leakage-proof uplift pile, which comprises a pile body and a pile head, wherein the lower end of the pile body is provided with a bottom plate, the bottom surface of the bottom plate is a first spherical surface, the lower surface of the bottom plate is provided with a boss matched with the pile head, the bottom surface of the boss is a second spherical surface, and the pile head is assembled by a plurality of shells with the same structure and size; the edge of the upper end of the sub-shell, which is matched with the first spherical surface, is a third spherical surface; the first spherical surface, the second spherical surface and the third spherical surface are all spherical centers with pile tip points of the pile head; the second spherical surface is provided with sliding grooves corresponding to the sub-shells one by one, the inner wall surface of the sub-shells is fixedly provided with sub-covers, guide rods are fixedly arranged above the sub-covers, the top ends of the guide rods are in sliding fit with the sliding grooves through sliding blocks, the spherical surface is matched with the sliding grooves, the guide rods and the structure forces the sub-shells to only execute rotary motion taking the pile tip points as pivot points, and concrete is prevented from leaking when the pile heads are not expanded in place.

Description

Leakage-proof anti-pulling pile

Technical Field

The invention belongs to the field of constructional engineering, and particularly relates to a leakage-proof uplift pile.

Background

The uplift pile is widely applied to the uplift resistance of large basements, the uplift resistance of high-rise buildings, the uplift resistance of offshore wharf platforms, anchor pile foundations of suspension bridges and cable-stayed bridges, pile foundations of large dock bottom plates, anchor pile foundations in static load test piles and the like. When a part of the underground structure of the building engineering is lower than the peripheral soil water level, uplift piles are required to be arranged to offset the uplift force generated by the water in the soil on the structure, so that the stability of the building structure is ensured.

The existing anti-floating pile is mainly manufactured in a cast-in-situ mode, the construction process is complex, and the construction efficiency is extremely low; moreover, because the geological conditions of different construction regions are different, the soil layer collapse phenomenon in the punching process is difficult to control; in addition, when the traditional construction method of the whole pile cast-in-situ anti-pulling pile is adopted, the poured concrete is easy to mix and dilute with the slurry water in the hole, so that the strength of the whole pile is difficult to ensure. In view of the above-mentioned drawbacks, although a new type of uplift pile is discussed in the prior art (CN 112227359B), the uplift pile can expand the pile head from the upper portion by using grouting pressure, so as to form an enlarged head and a cement stone body at the pile bottom, and the enlarged head portion of the uplift pile has no gap and does not depend on the pile body floating process to form the enlarged head, so that the structure is stable and reliable.

However, the pile head in the prior art has high limitation conditions on the pile foundation soil layer structure and grouting pressure, and when the pile head is applied to a soft soil layer or a scene with overlarge water content in the soil layer, the pile head is supported by the soil layer with lower supporting force, and the pile head is separated from the tail end of the pile body to move downwards in the grouting process (as shown in fig. 13), so that concrete leaks from the upper end of the pile head, and an enlarged head cannot be effectively formed; when the grouting pressure is applied to a hard soil layer, grouting pressure is increased to expand the pile head, but as concrete slurry directly impacts the lower part of the pile head, when the grouting pressure is excessive, the lower end of the pile head expands before the upper end (namely, a rotary expansion process around a pivot point B shown in fig. 14 occurs), so that concrete leaks from the lower end of the pile head, and an enlarged head cannot be effectively formed.

In addition, in the prior art, the upper end surface of the pile head and the lower surface of the boss are both in a plane structure, and the plane contact mode can form a good airtight space when the pile head is not expanded, but after the pile head is expanded by a certain extent (expanded according to the design mode), the arc-shaped inner edge of the upper end of the pile head sub-shell is in contact with the lower surface of the boss, and a gap is inevitably formed at the upper end of the pile head sub-shell by the structure of the plane and the arc edge in a matched mode, so that concrete slurry is leaked in advance.

Therefore, the invention aims to solve the technical problems, and provides the leakage-proof anti-pulling pile which can adapt to a full-type soil layer structure, has wide grouting pressure limiting conditions and can prevent the premature leakage of concrete slurry from the top or the bottom of the pile head.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a leakage-proof uplift pile which can prevent concrete slurry from leaking from a pile head at the initial stage of filling the concrete slurry into the pile head to form an enlarged head, so that the enlarged head with the upper part expanded at the bottom of the pile is reliably formed, and the technical problems in the prior art are effectively solved.

The present invention achieves the above technical object by the following technical means.

The leakproof anti-pulling pile comprises a prefabricated pile body and a pile head movably arranged at the bottom of the pile body, wherein the pile body comprises a bottom plate fixedly arranged at the lower end of the pile body, a boss matched with the pile head is arranged on the lower surface of the bottom plate, the pile head is formed by assembling a plurality of sub-shells with the same structure and size, and a grouting pipe sequentially penetrates through the bottom plate and mounting holes in the boss and stretches into an inner cavity of the pile head; the bottom surface of the bottom plate is a first spherical surface, the bottom surface of the boss is a second spherical surface, and the edge of the upper end of the sub-shell matched with the first spherical surface is a third spherical surface; the first spherical surface, the second spherical surface and the third spherical surface have the same sphere center A, and the sphere center A is a pile tip point of the pile head.

Further, the second spherical surface is provided with sliding grooves which are in one-to-one correspondence with the sub-shells, and the sliding grooves extend along the expanding direction of the sub-shells; the inner wall surface of the sub-shell is fixed with a sub-cover, a guide rod is fixed above the sub-cover, and the top end of the guide rod is in sliding fit with the chute through a sliding block.

Further, the axis of the guide rod is directed to the sphere center A, and the sliding block is matched with the sliding groove, so that the sub-shell can only perform rotary motion around the sphere center A.

Further, the root parts of the sub covers are positioned at the upper half parts of the sub shells, the sub covers of all the sub shells are spliced into a seamless cover body after being installed, and the seamless cover body divides the inner cavity of the pile head into an upper cavity communicated with the grouting pipe and a lower cavity isolated from the grouting pipe.

Further, the sub-cover includes a main body portion and lower and upper wall portions located at both sides of the main body portion and overlapped with the adjacent sub-cover.

Further, the upper surface of the lower half wall part and the lower surface of the lower half wall part form a superposed surface matched with the half wall part of the adjacent sub; at least the overlapping surface is a spherical surface taking the sphere center A as the sphere center.

Further, each of the sub-shells is provided with an inner notch and an outer notch at two side edges thereof respectively; the wall thickness of the corresponding sub-shell at the inner notch and the outer notch is half of the wall thickness of the rest part; the inner notch is complementary with the outer notch, so that the sub-shells are allowed to be spliced end to form a complete conical pile head.

Further, an inserting gap is formed between the root of the half wall part of the sub cover at the inner notch and the inner notch.

The invention has the following beneficial effects:

compared with the prior art, the matching of the first spherical surface and the third spherical surface in the invention allows the fluid seal between the bottom of the pile body and the inner cavity of the pile head to be maintained in the process of correctly expanding the pile head, and can prevent concrete from leaking outwards from the inner cavity of the pile head when the pile head is not expanded in place, so that the grouting pressure does not need to be increased in the grouting process to supplement the decompression caused by the concrete leakage, and the phenomenon of pile tip opening caused by overlarge grouting pressure is not caused naturally; the cooperation of the sliding groove and the guide rod can effectively prevent the pile head from generating pile-leaving motion along the axial direction of the pile body, meanwhile, the sliding groove is set to take the point A as the sphere center, and simultaneously, the guide rod with the axis pointing to the point A is matched, so that the sub-shell can be forced to only execute rotary motion taking the point A as the pivot point, and then the sub-shell is expanded in a correct mode; the setting of the sub-cover can effectively distribute static pressure provided by concrete slurry to the upper half part of the sub-shell, thereby ensuring the correct expansion mode of the pile head from the aspect of driving force; the means act together, so that two error expansion modes of pile head separation and pile tip opening are effectively overcome, the anti-pulling pile can adapt to more comprehensive coating structure working conditions, and meanwhile, the control requirement on grouting pressure is reduced. In addition, when the pile head is expanded in a correct mode, the first spherical surface and the third spherical surface can be always tightly attached, and the problem of gaps caused by the attachment of the arc-shaped edge and the plane can be avoided.

Drawings

FIG. 1 is a schematic diagram of a combination of a leak-proof pull-out-resistant form and a pile head;

FIG. 2 is a schematic view of a spherical bottom surface of a base plate and boss;

FIG. 3 is a schematic view of the arrangement of the chute on the boss;

FIG. 4 is an enlarged schematic view of a portion of the encircled portion of FIG. 3;

FIG. 5 is a schematic view of the closure of the sub-shell of the tape cover;

FIG. 6 is a three-dimensional schematic of a sub-shell of the tape cover;

FIG. 7 is a three-dimensional schematic view of a child cap;

FIG. 8 is a top view of FIG. 5;

FIG. 9 is a schematic view of a superimposed side of the sub-lid;

FIG. 10 is a top view of FIG. 6;

FIG. 11 is a schematic view of a star-shaped opening;

FIG. 12 is a schematic view of the sub-shell being rotationally expanded about the center of the sphere A;

FIG. 13 is a schematic diagram of a pile head of the prior art with pile separation;

fig. 14 is a schematic view of a prior art pile tip.

In the figure: the anti-leakage pile comprises a 1-anti-pulling pile body, a 2-pile body, a 21-bottom plate, a 211-first spherical surface, 212-mounting holes, 22-bosses, 221-second spherical surfaces, 222-sliding grooves, 3-grouting pipes, 4-pile heads, 41-sub-shells, 42-inner notches, 43-outer notches, 44-inner half walls, 45-outer half walls, 46-third spherical surfaces, 5-sub-covers, 51-lower half wall parts, 52-upper half wall parts, 53-overlapped surfaces, 6-guide posts and 61-sliding blocks.

Detailed Description

The invention will be further described with reference to the drawings and the specific embodiments, but the scope of the invention is not limited thereto.

As shown in fig. 1 and 2, the leak-proof anti-pulling pile of the invention comprises a prefabricated columnar pile body 2, wherein the pile body 2 comprises a bottom plate 21 fixedly arranged at the lower end, a boss 22 coaxial with the bottom plate 21 is arranged on the lower surface of the bottom plate 21, and a mounting hole 212 penetrating through the bottom plate 21 and the boss 22 simultaneously is arranged at the central position of the bottom plate 21. The mounting hole 212 is internally provided with a unidirectional grouting pipe 3, the outer wall of the grouting pipe 3 is in sealing arrangement with the inner wall of the mounting hole 212, and the grouting pipe 3 is arranged to be positioned relative to the mounting hole 212, for example, clamping elements such as clamping rings are respectively arranged at the positions of the grouting pipe 3, which are positioned at the upper part and the lower part of the bottom plate 21, so that the grouting pipe 3 is stable in the high-pressure grouting process and cannot be separated from the mounting hole 212, and similar positioning methods are also numerous in the prior art and are not repeated herein. The grouting pipe 3 can be a sleeve valve pipe or other structural forms capable of realizing high-pressure unidirectional grouting.

The lower part of the bottom plate 21 is movably provided with a pile head 4, and the pile head 4 is of a conical structure matched with the pile body 2.

The pile head 4 has a casing and a cavity enclosed by the casing. Wherein the housing is assembled from a plurality of sub-housings 41 as shown in fig. 6, and the housing is assembled from four sub-housings 41 in this embodiment, it should be understood that the number of sub-housings 41 defined herein is merely for convenience of illustration and is not the only way to define or prefer.

As shown in fig. 6, each sub-case 41 has the same shape and size, and each sub-case 41 is provided at both sides thereof (refer to sides extending in the direction of the bus bar of the conical structure) with an inner notch 42 and an outer notch 43 (here, the inner and outer are identified as being in accordance with the inner and outer of the conical structure), respectively. Accordingly, the wall thickness of the corresponding sub-shell 41 at the inner notch 42 and the outer notch 43 is half of the wall thickness of the remaining portion, thereby forming an outer half wall 45 and an inner half wall 44 at the inner notch 42 and the outer notch 43. The inner notch 42 is complementary to the outer notch 43, allowing the four sub-shells 41 to be spliced into one complete conical pile head 4; the diameter of the conical bottom of the conical pile head 4 formed when the inner notch 42 and the outer notch 43 are completely assembled and overlapped is not larger than the diameter of the pile body 2.

As shown in fig. 2 and 3, the boss 22 on the lower surface of the bottom plate 21 has a shape and size matching those of the inner cavity of the conical pile head 4, so as to allow the inner surfaces of the four sub-shells 41 to be completely fitted with the outer circumference of the boss 22.

As shown in fig. 2 and 3, the bottom surface of the bottom plate 21 is a spherical surface, i.e., a first spherical surface 211; the bottom surface of the boss 22 is also a spherical surface, namely a second spherical surface 221; the edge of the upper end of the sub-shell 41, which is in contact fit with the first spherical surface 211, is also a spherical surface, namely a third spherical surface 46; the first spherical surface 211, the second spherical surface 221 and the third spherical surface 46 all have the same spherical center a, and the spherical center a is the conical point of the pile head 4. Therefore, when the pile head 4 is expanded in the correct manner as shown in fig. 12, that is, the sub-casing 41 is expanded outward in a manner of rotating around the center a, the first spherical surface 211 and the third spherical surface 46 can always keep close fit, without the problem of gaps caused by the fit of the arc-shaped edge and the plane.

In order to enable the pile head 4 to be correctly expanded in various situations, the present embodiment is further modified as follows:

as shown in fig. 3 and 4, the second spherical surface 221 is provided with a plurality of sliding grooves 222, and the sliding grooves 222 are in one-to-one correspondence with the sub-shells 41; on the other hand, a sub-cover 5 is fixed on the inner wall surface of the sub-housing 41, a guiding rod 6 is fixedly arranged above the sub-cover 5, the axis of the guiding rod 6 points to the sphere center a, and the top end of the guiding rod 6 is in sliding fit with the sliding groove 222 through a sliding block 61. The cooperation of the slide 61 with the slide 222 restricts the sub-casing 41 to perform only a rotational movement about the centre of sphere a, and in particular, by using a slide 61 having a larger cross-sectional dimension than the guide bar 6, for example, a spherical or square slide 61 can be used to cooperate with the spherical or T-shaped slide 222, thereby enabling the slide 222 to drag the sub-casing 41 by the slide 61 and the guide bar 6, preventing the pile head 4 from being lifted off.

As shown in fig. 1, 5, 6, 8 and 9, the connection part (hereinafter referred to as root) of the sub-cover 5 and the corresponding sub-casing 41 is located at the upper half part of the sub-casing 41, and when the sub-casing 41 is spliced into the conical pile head 4 in the initial state, the sub-covers 5 on the inner wall surfaces of all the sub-casings 41 are spliced into a seamless cover body, and the seamless cover body separates the inner cavity of the pile head 4 into an upper cavity communicated with the grouting pipe 3 and a lower cavity isolated from the grouting pipe 3.

Thus, at the initial stage of grouting, after grouting from the grouting pipe 3, concrete grout is first trapped in the upper chamber, and static pressure is applied to the upper half side wall of the sub-housing 41 and the sub-cover 5 after the upper chamber is filled; and since the root of the sub-cover 5 is fixed to the upper half of the sub-shell 41, the static pressure applied to the sub-cover 5 will also be transmitted to the upper half of the sub-shell 41 through the root, thereby causing the sub-shell 41 to rotationally expand about the center of sphere a. This arrangement allows construction without regard to whether the grouting pressure is excessive, because the concrete receives and transmits the downward impact force by the sub-cover 5 to the upper half of the sub-housing 41, thereby converting into an expanding pushing force of the upper half of the sub-housing 41.

As shown in fig. 6 to 10, the sub-cap 5 includes a main body portion and two half wall portions (i.e., a lower half wall portion 51 and an upper half wall portion 52) located on both sides of the main body portion and overlapped with the adjacent sub-cap 5; the lower half wall 51 is located at one side of the inner notch 42, and a plugging gap 54 is formed between the root of the lower half wall and the inner notch 42 as shown in fig. 6, and the plugging gap 54 is used for overlapping and matching the inner half wall 44 of the adjacent sub-shell 41 with the outer half wall 45 of the current sub-shell 41. It will be appreciated that the insertion gap 54 is present only on one side of the inner gap 42, but is not limiting as to the arrangement of the lower and upper wall portions 51, 52, i.e. the positions of the wall portions may be interchanged. The upper surface of the lower half wall portion 51 and the lower surface of the upper half wall portion 52 form a superposed surface 53 which is matched with the upper and lower half wall portions of the adjacent sub-cover 5; at least the overlapping surface 53 is a spherical surface having the center of the sphere a as the center of the sphere, in other words, the upper and lower surfaces of the main body portion may not be spherical surfaces. This arrangement allows the adjacent sub-caps 5 to remain partially superimposed by the half-wall portions when the sub-shells 41 are expanded, and to form only the star-shaped opening 7 as illustrated in fig. 11; the star-shaped opening 7 is advantageous for retarding the opening speed of the fluid passage between the upper and lower chambers, thereby maintaining the static pressure difference of the concrete slurry applied to the upper and lower halves of the sub-housing 4.

The examples are preferred embodiments of the present invention, but the present invention is not limited to the above-described embodiments, and any obvious modifications, substitutions or variations that can be made by one skilled in the art without departing from the spirit of the present invention are within the scope of the present invention.

Claims (6)

1. The utility model provides a leak protection anti-floating pile, includes prefabricated pile body (2) and pile head (4) of activity setting in pile body (2) bottom, pile body (2) including fixed bottom plate (21) that sets up in its lower extreme, bottom plate (21) lower surface is equipped with boss (22) with pile head (4) assorted, pile head (4) are assembled by a plurality of structures, sub-shells (41) that the size is the same, grouting pipe (3) pass mounting hole (212) on bottom plate (21) and boss (22) in proper order and stretch into pile head (4) inner chamber; the device is characterized in that the bottom surface of the bottom plate (21) is a first spherical surface (211), the bottom surface of the boss (22) is a second spherical surface (221), and the edge of the upper end of the sub-shell (41) matched with the first spherical surface (211) is a third spherical surface (46); the first spherical surface (211), the second spherical surface (221) and the third spherical surface (46) have the same sphere center A, and the sphere center A is a pile tip point of the pile head (4);

the second spherical surface (221) is provided with sliding grooves (222) which are in one-to-one correspondence with the sub-shells (41), and the sliding grooves (222) extend along the expanding direction of the sub-shells (41); a sub cover (5) is fixed on the inner wall surface of the sub shell (41), a guide rod (6) is fixed above the sub cover (5), and the top end of the guide rod (6) is in sliding fit with the chute (222) through a sliding block (61);

the axis of the guide rod (6) points to the sphere center A, the sliding block (61) is matched with the sliding groove (222), and the sub-shell (41) is limited to only execute rotary motion around the sphere center A.

2. The leakage-proof and uplift pile according to claim 1, characterized in that the root of the sub-cover (5) is located at the upper half of the sub-shell (41), the sub-covers (5) of all the sub-shells (41) are spliced into a seamless cover after installation, and the seamless cover separates the inner cavity of the pile head (4) into an upper cavity communicated with the grouting pipe (3) and a lower cavity isolated from the grouting pipe (3).

3. The leakage-proof and uplift pile according to claim 2, characterized in that the sub-cover (5) comprises a main body part and a lower half-wall part (51) and an upper half-wall part (52) located on both sides of the main body part and overlapping with the adjacent sub-cover (5).

4. A leakproof uplift pile according to claim 3, characterized in that the upper surface of the lower half-wall part (51) and the lower surface of the upper half-wall part (52) form a superimposed surface (53) matching the half-wall parts of the adjacent sub-covers (5); at least the overlapping surface (53) is a spherical surface with the center of the sphere A as the center of the sphere.

5. The leakage-proof and uplift pile according to claim 4, characterized in that each of said sub-shells (41) is provided with an inner notch (42) and an outer notch (43) at its two lateral edges, respectively; the wall thickness of the corresponding sub-shell (41) at the inner notch (42) and the outer notch (43) is half of the wall thickness of the rest part; the inner notch (42) is complementary to the outer notch (43) so as to allow the sub-shells (41) to be spliced end to end into a complete conical pile head (4).

6. The leakage-proof and uplift pile according to claim 5, characterized in that the sub-cover (5) has a plug-in gap (54) between the root of the half-wall portion at the inner gap (42) and the inner gap (42).