CN108978646B

CN108978646B - Bottom expanding self-expansion device

Info

Publication number: CN108978646B
Application number: CN201811069396.XA
Authority: CN
Inventors: 陈娟; 何四春; 柯昌君; 李昊洋; 刘鸿伟; 朱凌云; 刘子丹; 万小青; 陈语涵
Original assignee: Jingzhou Huasheng New Material Co ltd; Yangtze University
Current assignee: Jingzhou Huasheng New Material Co ltd; Yangtze University
Priority date: 2018-09-13
Filing date: 2018-09-13
Publication date: 2022-02-11
Anticipated expiration: 2038-09-13
Also published as: CN108978646A

Abstract

The invention discloses a device for expanding bottom and expanding automatically, which comprises an outer wall of an automatic expansion box body and an I-shaped structure; the self-expansion box body is filled with expansion materials, and the self-expansion box body and the I-shaped structure limit the upward and downward expansion force of the expansion materials, so that the expansion materials can only horizontally expand. The pile foundation expansion device can be filled with the expansion material, the expansion head is formed by utilizing the expansion performance of the expansion material, the formation of the expansion head is free of pollution such as noise, dust and the like, and the pile foundation expansion device is economical and practical, convenient to operate and wide in application range, and can well meet the design requirement of the pile foundation with higher requirement on the pulling resistance of the bearing capacity.

Description

Bottom expanding self-expansion device

Technical Field

The invention belongs to the technical field of civil engineering, relates to the field of constructional engineering, and particularly relates to a bottom expanding self-expansion device.

Background

With the continuous development of engineering construction, the bearing capacity of each large building on the foundation is higher and higher, and in order to increase the bearing capacity of a single pile, the method for using the pedestal pile foundation in the construction of the foundation is an economic and effective method. The pedestal pile is improved and perfected on the basis of a pile with a uniform cross section, and when construction is carried out, after a design bearing layer is excavated, pedestal expansion is carried out on the bottom of a pile body, and concrete is poured to form a pile after the pedestal diameter meeting the design requirement, so that a concrete expanded head at the bottom is formed. The foundation of the pedestal pile commonly used in China at present has the forms of cast-in-situ bored pile, blasting pile, shock-impact pedestal pile and the like.

The pedestal pile foundation can realize small diameter and large bearing, but the traditional pedestal pile foundation has a plurality of problems, for example, the formation of an enlarged head is often completed by the aid of large machinery; after the enlarged head is formed, the hole wall has poor stability and is easy to collapse; the compactness and impermeability of pile body concrete are poor, and harmful substances can directly erode the concrete easily; pile body defects such as pile breakage, hole wall collapse, pile body mud inclusion, honeycomb pitted surface and the like are easily caused in the construction process; a great deal of noise and dust pollution is accompanied during construction; the pile forming efficiency is low and the cost is high.

Disclosure of Invention

In view of the above problems in the prior art, the present invention provides a device for bottom-expanding self-expansion, which can be filled with an expansion material, and an expanded head is formed by utilizing the expansion property of the expansion material. The device limits the upward and downward expansion force of the expansion material, so that the expansion material can only expand horizontally, the formed expanded head is large in size, and the design requirement of a pile foundation with higher requirement on the pulling resistance of the bearing capacity can be well met.

Therefore, the invention adopts the following technical scheme:

a device for expanding bottom and expanding automatically comprises an outer wall of an expanding box body and an I-shaped structure; the self-expansion box body is filled with expansion materials, and the self-expansion box body and the I-shaped structure limit the upward and downward expansion force of the expansion materials, so that the expansion materials can only horizontally expand.

Preferably, the outer wall of the self-expansion box body is equally cut into a plurality of blocks, and the lower end of the self-expansion box body is completely cut open, so that the lower end can move freely; the upper end is not completely cut and remains connected into a whole.

Preferably, the outer wall of the self-expanding box is cut into 8 equal parts.

Preferably, the I-shaped structure comprises an upper circular steel plate, a lower circular steel plate and a middle steel bar, and two ends of the middle steel bar are respectively welded with the upper circular steel plate and the lower circular steel plate; the diameter of the upper round steel plate is 0.2mm-0.5mm smaller than the inner diameter of the outer wall of the self-expansion box body; the diameter of the lower round steel plate is 10mm-20mm larger than the outer diameter of the outer wall of the self-expansion box body.

Preferably, the outer diameters of the upper and lower bottoms of the device are 50mm-500 mm.

Preferably, the diameter of the middle reinforcing steel bar is 20mm-35mm, the number of the middle reinforcing steel bars is 2-16, and the middle reinforcing steel bars are symmetrically welded near the centers of the upper steel plate and the lower steel plate.

Preferably, the self-expansion box body is provided with 1-2 grouting holes with the aperture of 5mm-20 mm.

Preferably, the device has a length of 100mm to 1000 mm.

Further, the wall thickness of the self-expansion tank is determined according to the expansion force provided by the adopted expansion material, so that the expansion material forms a stable expansion head after being expanded.

Furthermore, the device is connected to the lower part of the pile, and is countersunk along with the pile, and the expanded base is formed through expansion of the expansion material.

Compared with the prior art, the invention has the beneficial effects that:

(1) mechanical bottom expanding is not needed, and disturbance to undisturbed soil and soil around a pile foundation is reduced.

(2) The expanded head is formed by the expansion material, and simultaneously the upper pile foundation can be constructed, so that the construction time of the pedestal pile is reduced.

(3) The hole wall of the expanded head formed by the expansion material is stable and is not easy to collapse.

(4) The intumescent material expands underground and does not generate much noise and dust when it expands.

Drawings

FIG. 1 is a front view of an apparatus for bellout self-expansion according to the present invention.

FIG. 2 is a top view of an apparatus for belling self-expansion according to the present invention.

FIG. 3 is a schematic perspective view of an I-shaped structure of a device for bottom-expanding self-expansion according to the present invention.

Description of reference numerals: 1. grouting holes; 2. cutting seams on the outer wall of the self-expansion box body; 3. an upper circular steel plate; 4. reinforcing steel bars; 5. a lower circular steel plate.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and specific embodiments, which are provided for illustration only and are not to be construed as limiting the invention.

The invention mainly aims at that the formation of the expanding head in the prior art often needs large machinery; the compactness and impermeability of pile body concrete are poor, and harmful substances can directly erode the concrete easily; pile body defects such as pile breakage, hole wall collapse, pile body mud inclusion, honeycomb pitted surface and the like are easily caused in the construction process; the noise and dust pollution is big, and a device for bottom expanding self-expansion is provided, and the core idea is as follows: the self-expansion box body is made of steel and other materials, the expansion material is directly placed in the self-expansion box body after the factory prefabrication is completed before the construction, and the self-expansion box body is countersunk along with the upper part of the pile, so that the operation can be completed manually without large machinery; the expansive force generated by the expansive material forms an expanded head, and the expansive force always exists and extrudes the surrounding soil body to form a stable expanded head.

Examples

As shown in fig. 1, a device for expanding bottom and expanding itself comprises an outer wall of a self-expansion box body and an I-shaped structure; the self-expansion box body is filled with expansion materials, and the self-expansion box body and the I-shaped structure limit the upward and downward expansion force of the expansion materials, so that the expansion materials can only horizontally expand. An equal cutting seam 2 is arranged on the outer wall of the expansion tank, wherein the bottom is completely cut, and the upper part is left uncut. A grouting hole 1 is formed in the self-expansion tank and mainly used for grouting expansion materials into the self-expansion tank through the grouting hole.

As shown in fig. 2, the cutting criteria for equally dividing the slit 2 from the outside of the expansion tank is to determine an x-axis direction in a plane parallel to the upper and lower circular steel plates and to cut the slit at 0, 45, 90, 135, 180, 225, 270, 315 degrees with reference to the x-axis direction.

As shown in fig. 3, the i-shaped structure inside the self-expansion tank is composed of an upper circular steel plate 3, a reinforcing steel bar 4 and a lower circular steel plate 5. The reinforcing steel bar 4 is connected with the upper circular steel plate 3 and the lower circular steel plate 5 in a welding connection mode. The diameter of the upper round steel plate 3 is 0.2mm-0.5mm smaller than the inner diameter of the outer wall of the self-expansion box body; the diameter of the lower round steel plate 5 is 10mm-20mm larger than the outer diameter of the outer wall of the self-expansion box body.

During construction, the expansion device is welded at the bottom of the pile, before the pile is hoisted into the hole, the expansion material is poured into the hole through the grouting hole 1, and then the device is sealed and the hole is drilled along with the pile.

Here, the specific dimensions of the device are: the outer diameter of the device is 50mm-500mm, and the length of the device is 100mm-1000 mm; the diameter of the steel bars 4 is 20mm-35mm, and the number of the steel bars is 2-16; the number of the grouting holes 1 is 1-2, and the aperture is 5mm-20 mm.

The above description is only exemplary of the present invention and should not be taken as limiting the invention, as any modification, equivalent replacement, or improvement made within the spirit and scope of the present invention should be included in the present invention.

Claims

1. The utility model provides a device for expanding end is from inflation, includes self-expansion box outer wall and I shape structure, its characterized in that: the self-expansion box body and the I-shaped structure limit the upward and downward expansion force of the expansion material, so that the expansion material can only horizontally expand;

the outer wall of the self-expansion box body is equally cut into a plurality of blocks, and the lower end of the self-expansion box body is completely cut open, so that the lower end can move freely; the upper end is not completely cut and is kept connected into a whole;

the I-shaped structure comprises an upper circular steel plate, a lower circular steel plate and a middle steel bar, wherein two ends of the middle steel bar are respectively welded with the upper circular steel plate and the lower circular steel plate; the diameter of the upper round steel plate is 0.2mm-0.5mm smaller than the inner diameter of the outer wall of the self-expansion box body; the diameter of the lower round steel plate is 10mm-20mm larger than the outer diameter of the outer wall of the self-expansion box body;

the outer wall of the self-expansion box body is cut into 8 pieces in equal parts;

the outer diameters of the upper and lower bottoms of the device are all 50-500 mm.

2. An apparatus for belling self-expansion according to claim 1, wherein: the diameter of the middle steel bars is 20-35 mm, the number of the middle steel bars is 2-16, and the middle steel bars are symmetrically welded near the centers of the upper and lower circular steel plates.

3. An apparatus for belling self-expansion according to any one of claims 1 to 2, wherein: 1-2 grouting holes with the aperture of 5-20 mm are formed in the self-expansion box body.

4. An apparatus for belling self-expansion according to claim 3, wherein: the length of the device is 100mm-1000 mm.

5. An apparatus for belling self-expansion according to claim 4, wherein: the wall thickness of the self-expansion tank is determined according to the expansion force provided by the adopted expansion material, so that the expansion material forms a stable expansion head after being expanded.

6. An apparatus for belling self-expansion according to claim 5, wherein: the device is connected to the lower part of the pile, counter bores are formed along with the pile, and a club-footed foundation is formed through expansion of expansion materials.