Complex deep foundation pit support column underpinning system and construction method

Abstract

The present invention relates to a complex deep foundation pit support column replacement system and construction method, comprising the following steps: according to the position of the column to be replaced, passing the steel pipe through the steel sleeve on the connecting ring plate to the designed position; processing several sections of the replacement column; fixing the "J"-shaped clamp on both sides of each support; installing the replacement column; and removing the column to be replaced. The beneficial effects of the present invention are: fast construction speed, all assembly is done on site, and construction efficiency is improved; the replacement column is replaced by the replacement column between each support, the bottom foundation of the replacement column is fixed by interlacing steel pipes and connecting ring plates, the top structure of the steel pipe is welded into one by steel bars, and concrete is poured, and finally the steel pipe is post-grouting construction is carried out to improve the bearing capacity of the foundation; the replacement column and the support adopt the "J"-shaped clamp quick connection structure, which improves construction efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of underground engineering, and in particular relates to a complex deep foundation pit support column underpinning system and a construction method. Background Art

[0002] With economic development and social progress, the construction level of my country's construction projects has continued to improve, and the difficulty of foundation construction in related projects has also increased. To ensure the smooth construction of complex deep foundation pits, support structures are usually used in the foundation pits. Generally, complex deep foundation pit support adopts ground-connected walls + bracing. In engineering construction, in order to shorten the construction period and reduce the construction cost, the foundation pit support project of complex deep foundation pits is sometimes constructed before the main structure drawings of the building are fully determined. However, after the complex deep foundation pit is excavated, due to various reasons, the main structural pile foundations or beams and columns of some projects may be adjusted, resulting in the position of the completed support columns and piles and the main pile foundations or beams and columns. Therefore, it is very important to resolve the conflict between the columns and the main structure.

[0003] To sum up, for the current construction of supporting column replacement in foundation pit, it is very important to seek a complex deep foundation pit support column replacement system and construction method with reliable quality, simple operation and high safety. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a complex deep foundation pit support column underpinning system and construction method.

[0005] This complex deep foundation pit support column underpinning system includes: ground-connected walls, supports, "X"-shaped clamps, underpinning columns, columns, connecting ring plates, steel bars, steel pipes and soil;

[0006] Several supports are horizontally arranged between the ground-connected walls, with the bottom ends of the columns extending into the soil. The columns include the columns to be replaced. The replacement columns are composed of several segments, with one segment being located between two adjacent supports. Steel pipes are located in the soil, with grouting holes provided on the steel pipes. Grouting is poured into the soil outside the grouting holes. A connecting ring plate is provided at the top end of the steel pipe. A segment of the replacement column is also located between the lowest support and the connecting ring plate. The connecting ring plate is provided with a concrete grouting port.

[0007] Two "J"-shaped clamps are symmetrically fixed on each support, and both ends of the supporting column segment between the supports are provided with "J"-shaped steel column feet. The top of the supporting column segment between the support and the connecting ring plate is provided with an "J"-shaped steel column foot, and the bottom end is provided with an enlarged "J"-shaped steel column foot; the "J"-shaped steel column foot is connected to the two "J"-shaped clamps on the support, and the enlarged "J"-shaped steel column foot is connected to the connecting ring plate.

[0008] Preferably: a concrete grouting port is provided in the center of the connecting ring plate, and a steel sleeve and a threaded rod are provided around the concrete grouting port on the connecting ring plate; a threaded section is provided on the top of the steel pipe, and a pointed plug is provided on the bottom; the steel pipes are divided into three groups, namely the first group of steel pipes, the second group of steel pipes and the third group of steel pipes, and the grouting holes of each group of steel pipes are of different heights; each group of steel pipes includes two identical steel pipes, and the two steel pipes in each group of steel pipes are symmetrically inserted into the bottom of the connecting ring plate through the steel sleeve, and several steel bars are welded to the top structure of the steel pipes.

[0009] As a preferred embodiment: two I-shaped clamps fixed on the same support are connected by tension screws, and a channel steel base is provided on the I-shaped clamp; the I-shaped steel column foot is connected to the channel steel base on the I-shaped clamp by high-strength bolts, and a steel pad is also provided on the inner wall of the lower surface of the I-shaped clamp connection support; the expanded I-shaped steel column foot includes an ear plate, and a threaded rod is provided on the connecting ring plate, and the threaded rod is fixedly connected to the ear plate of the expanded I-shaped steel column foot.

[0010] As a preference: the size of the I-shaped steel column foot matches the size of the supporting column, and the inner wall spacing of the I-shaped steel column foot is greater than the length of the tension screw; the size of the expanded I-shaped steel column foot matches the connecting ring plate, and the inner wall spacing of the expanded I-shaped steel column foot is greater than the distance between the steel sleeves.

[0011] As a preference, the X-shaped clamp and the connecting ring plate connected to each support are located on the same vertical axis, and the several sections of the supporting column are arranged on the same vertical axis.

[0012] The construction method of this complex deep foundation pit support column underpinning system includes the following steps:

[0013] Step 1: Positioning the underpinning columns: Install the connecting ring plate according to the position of the columns to be replaced, pass the steel pipes through the steel sleeves on the connecting ring plate and drive them to the designed position, and excavate the soil around the steel pipes; weld the steel pipes and the connecting ring plate into a whole with steel bars; pour concrete through the concrete grouting ports of the connecting ring plate; finally, perform post-grouting construction on the first, second, and third groups of steel pipes in sequence to form a grouting body;

[0014] Step 3: Processing the underpinning columns: Process several sections of underpinning columns. Set an enlarged "X"-shaped steel column foot at the bottom end of the underpinning column connected to the connecting ring plate, set an "X"-shaped steel column foot at the top end, and set an "X"-shaped steel column foot at both ends of the remaining underpinning columns.

[0015] Step 4: Install the "X" shaped clamp: Pull the "X" shaped clamp to both sides of each support;

[0016] Step 5. Install the replacement column: Install the replacement column, fix the I-shaped steel column foot to the I-shaped clamp, and expand the I-shaped steel column foot to fix it to the connecting ring plate.

[0017] Step 6. Remove the columns to be replaced: Remove the columns to be replaced.

[0018] Preferably, in step 1: the depth of excavating the soil around the steel pipe is 0.8m to 1.1m.

[0019] Preferably, in step four: a steel pad is provided on the inner wall of the lower surface of the support connected to the I-shaped clamp, the I-shaped clamp is clamped on both sides of each support, and then fixed by tensioning screws.

[0020] The beneficial effects of the present invention are:

[0021] 1) The complex deep foundation pit support column underpinning system of the present invention has the "J"-shaped steel clamps, steel columns, etc. which are all prefabricated in the factory, with fast construction speed. They are all assembled on site, thus improving construction efficiency.

[0022] 2) The complex deep foundation pit support column underpinning system of the present invention replaces the columns to be replaced by replacement columns between each support. The bottom foundation of the replacement column is fixed with steel pipes and connecting ring plates. The top structure of the steel pipe is welded into one piece with steel bars and poured with concrete. Finally, the steel pipe is post-grouting constructed to improve the bearing capacity of the foundation.

[0023] 3) The replacement column and the support of the present invention adopt an I-shaped clamp quick connection structure, which improves construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a cross-sectional diagram of the support column underpinning system for a complex deep foundation pit;

[0025] Figure 2 It is a schematic cross-sectional view of the connection part of the underpinning column foundation;

[0026] Figure 3 It is a plan view of the connecting ring plate;

[0027] Figure 4 This is a schematic diagram of the three-dimensional sample of the connecting ring plate;

[0028] Figure 5 It is a schematic diagram of the steel pipe sample;

[0029] Figure 6 It is a schematic diagram of the steel pipe layout;

[0030] Figure 7 This is a schematic diagram of the cross-section of the "X"-shaped clamp and support fixation;

[0031] Figure 8 This is a schematic diagram of the "X"-shaped hoop and support fixing facade;

[0032] Figure 9 This is a schematic diagram of the underpinning column;

[0033] Figure 10 This is a schematic diagram of the connection section of the underpinning column foundation;

[0034] Figure 11 This is a plan view of the "X"-shaped steel column foot supporting the column;

[0035] Figure 12 It is a construction process flow chart of the present invention.

[0036] In the figure: ground-connected wall 1, support 2, column to be replaced 3, I-shaped clamp 4, replacement column 5, column 6, threaded rod 7, connecting ring plate 8, steel bar 9, grouting body 10, steel pipe 11, soil 12, ear plate 13, grouting hole 14, concrete grouting port 15, steel sleeve 16, threaded section 17, first group of steel pipes 18, second group of steel pipes 19, third group of steel pipes 20, high-strength bolts 21, I-shaped steel column foot 22, channel steel base 23, steel pad 24, tension screw 25, expanded I-shaped steel column foot 26, pointed end plug 27. DETAILED DESCRIPTION

[0037] The present invention will be further described below with reference to the following examples. The following examples are provided only to facilitate understanding of the present invention. It should be noted that, without departing from the principles of the present invention, it is possible for a person skilled in the art to make various modifications to the present invention, and such improvements and modifications fall within the scope of the claims of the present invention.

[0038] Example 1

[0039] As an example, Figures 1 to 11 As shown, a complex deep foundation pit support column underpinning system includes: a ground-connected wall 1, a support 2, an X-shaped clamp 4, an underpinning column 5, a column 6, a connecting ring plate 8, steel bars 9, a steel pipe 11 and soil 12;

[0040] like Figure 1 and Figure 2 As shown, several supports 2 are horizontally arranged between the ground-connected walls 1, and the bottom ends of the columns 6 extend into the soil 12. The columns 6 include the columns 3 to be replaced; the underpinning columns 5 include several segments, and one segment is provided between two adjacent supports 2. A steel pipe 11 is provided in the soil 12, and a grouting hole 14 is provided on the steel pipe 11. Grouting body 10 is poured in the soil outside the grouting hole 14 to improve the bearing capacity of the foundation of the underpinning column 5; a connecting ring plate 8 is provided at the top end of the steel pipe 11, and a segment of the underpinning column 5 is also provided between the support 2 with the lowest elevation and the connecting ring plate 8.

[0041] like Figures 3 to 6As shown, a concrete grouting port 15 is provided in the center of the connecting ring plate 8, and a steel sleeve 16 and a threaded rod 7 are provided around the concrete grouting port 15 on the connecting ring plate 8; a threaded section 17 is provided on the top of the steel pipe 11, and a pointed plug 27 is provided at the bottom; the steel pipes 11 are divided into three groups, namely the first group of steel pipes 18, the second group of steel pipes 19 and the third group of steel pipes 20, and the grouting holes 14 of each group of steel pipes 11 are at different heights, so that grouting bodies 10 are formed at different heights in the soil 12; each group of steel pipes 11 includes two identical steel pipes 11, and the two steel pipes 11 in each group of steel pipes 11 are symmetrically inserted into the bottom of the connecting ring plate 8 through the steel sleeve 16. Several steel bars 9 are welded to the top structure of the steel pipe 11, so that the steel pipe 11, the steel sleeve 16 and the connecting ring plate 8 are welded into a whole, thereby improving the supporting force of the foundation of the replacement column 5.

[0042] like Figure 7 and Figure 8 As shown, two "X"-shaped clamps 4 are symmetrically clamped on each support 2. The clamping width of the "X"-shaped clamp 4 is 3cm to 5cm higher than the height of the support 2, ensuring that the "X"-shaped clamp 4 can be quickly clamped on the support 2. The inner wall of the "X"-shaped clamp 4 connected to the lower surface of the support 2 is also provided with a steel pad 24. The "X"-shaped clamp 4 and the connecting ring plate 8 connected to each support 2 are located on the same vertical axis, so that several segments of the replacement column 5 are located on the same vertical axis, forming a vertical support effect that can replace the column 3 to be replaced.

[0043] like Figure 9 and Figure 11 As shown, both ends of the subsection of the replacement column 5 arranged between the supports 2 are provided with an I-shaped steel column foot 22, the top of the subsection of the replacement column 5 arranged between the support 2 and the connecting ring plate 8 is provided with an I-shaped steel column foot 22, and the bottom end is provided with an enlarged I-shaped steel column foot 26; the I-shaped steel column foot 22 is connected to the two I-shaped clamps 4 on the support 2, and the enlarged I-shaped steel column foot 26 is connected to the connecting ring plate 8.

[0044] like Figure 2 and Figure 7 As shown, two I-shaped clamps 4 fixed on the same support 2 are connected by a tension screw 25, and a channel steel base 23 is provided on the I-shaped clamp 4; the I-shaped steel column foot 22 is connected to the channel steel base 23 on the I-shaped clamp 4 by a high-strength bolt 21; the expanded I-shaped steel column foot 26 includes an ear plate 13, and a threaded rod 7 is provided on the connecting ring plate 8, and the threaded rod 7 is fixedly connected to the ear plate 13 of the expanded I-shaped steel column foot 26.

[0045] The I-shaped steel column foot 22 matches the size of the supporting column 5, and the inner wall spacing of the I-shaped steel column foot 22 is greater than the length of the tension screw 25; the size of the expanded I-shaped steel column foot 26 matches the connecting ring plate 8, and the inner wall spacing of the expanded I-shaped steel column foot 26 is greater than the distance between the steel sleeves 16.

[0046] Example 2

[0047] As another example, Figure 12 As shown, the method for underpinning a complex deep foundation pit support column according to the complex deep foundation pit support support column underpinning system proposed in the first embodiment includes the following steps:

[0048] Step 1: Positioning the underpinning column: According to the position of the column 3 to be replaced, the foundation of the underpinning column 5 and the position of the support 2 are positioned.

[0049] Step 2: Construction of the underpinning column pile foundation: The underpinning column 5 foundation is fixed with steel pipe 11 and connecting ring plate 8. The top structure of the steel pipe 11 is welded into one piece by steel bars 9 and poured with concrete. Finally, the steel pipe 11 is post-grouting to improve the bearing capacity of the foundation.

[0050] Specifically, six steel sleeves 16 and four threaded rods 7 are provided on the connecting ring plate 8, and the steel sleeves 16 and threaded rods 7 are evenly arranged on the connecting ring plate 8; a concrete grouting port 15 is provided in the middle of the connecting ring plate 8; the steel pipes 11 are divided into three groups, namely a first group of steel pipes 18, a second group of steel pipes 19, and a third group of steel pipes 20, wherein each group includes two steel pipes 11, and grouting holes 14 of different heights are provided for the steel pipes 11 of different groups, and grouting holes 14 of the same height are provided for the steel pipes 11 of the same group. A threaded section 17 is provided on the top of the steel pipe 11, and a pointed plug 27 is provided on the bottom; two steel pipes 11 in the first group of steel pipes 18, the second group of steel pipes 19, and the third group of steel pipes 20 are symmetrically inserted into the steel sleeve 16 respectively;

[0051] After the steel pipe 11 is symmetrically driven to the designed position by a vibrating hydraulic pile driver, the soil 12 around the steel pipe 11 is excavated to a depth of 0.8m to 1.1m; the elevation and position of the connecting ring plate 8 are adjusted; the steel pipe 11, the steel sleeve 16, and the connecting ring plate 8 are welded into a whole through the steel bar 9; after the welding of the steel bar 9 is completed, formwork is supported, and concrete is poured through the concrete grouting port 15 of the connecting ring plate 8 and maintained; finally, the grouting machine is used to connect the threaded section 17 set at the top of the steel pipe 11 to carry out post-grouting construction, wherein the first group of steel pipes 18, the second group of steel pipes 19, and the third group of steel pipes 20 are post-grouting construction in sequence to form three groups of grouting bodies 10 of different depths.

[0052] Step 3: Processing of underpinning columns: Process several sections of underpinning columns 5. The underpinning columns 5 are steel columns. An enlarged "I"-shaped steel column foot 26 is set at the bottom end of the underpinning column 5 connected to the connecting ring plate 8, and an "I"-shaped steel column foot 22 is set at the top end. The remaining underpinning columns 5 are all provided with "I"-shaped steel column feet 22 at both ends.

[0053] Step 4. Processing and installation of the "J"-shaped clamp: The "J"-shaped clamp 4 is made of thick steel plate, and a channel steel base 23 is set on each half of the "J"-shaped clamp 4; the "J"-shaped clamp 4 is 3cm to 5cm higher than the height of the support 2 to ensure that the "J"-shaped clamp 4 can be quickly clamped on the support 2. The "J"-shaped clamps 4 are fixed to each other by tension screws 25, and a steel pad 24 is set at the bottom of the "J"-shaped clamp 4.

[0054] Step 5, installation of the underpinning column: Install the underpinning column 5, fix the I-shaped steel column foot 22 with the channel steel base 23 on the I-shaped clamp 4 through high-strength bolts 21; expand the I-shaped steel column foot 26 and connect it with the threaded rod 7 on the connecting ring plate 8 with high-strength bolts.

[0055] Step 6: Remove the supporting column to be replaced: After the installation of the supporting column 5 is completed, remove the supporting column 3 to be replaced.

Claims

1. A complex deep foundation pit support column underpinning system, characterized in that: include: Ground-connected wall (1), support (2), "X"-shaped hoop (4), supporting column (5), column (6), connecting ring plate (8), steel bar (9), steel pipe (11) and soil (12); Several supports (2) are horizontally arranged between the ground-connected walls (1), the bottom ends of the columns (6) extend into the soil (12), and the columns (6) include the columns to be replaced (3); the replacement columns (5) include several segments, one segment is provided between two adjacent supports (2), a steel pipe (11) is provided in the soil (12), a grouting hole (14) is provided on the steel pipe (11), and a grouting body (10) is poured in the soil outside the grouting hole (14); a connecting ring plate (8) is provided at the top end of the steel pipe (11), and a segment of the replacement column (5) is also provided between the support (2) with the lowest elevation and the connecting ring plate (8); a concrete grouting port (15) is provided on the connecting ring plate (8); Two "J"-shaped clamps (4) are symmetrically clamped on each support (2), and both ends of the subsection of the supporting column (5) between the supports (2) are provided with "J"-shaped steel column feet (22). The top of the subsection of the supporting column (5) between the support (2) and the connecting ring plate (8) is provided with a "J"-shaped steel column foot (22), and the bottom is provided with an enlarged "J"-shaped steel column foot (26); the "J"-shaped steel column foot (22) is connected to the two "J"-shaped clamps (4) on the support (2). The expanded "F"-shaped steel column foot (26) is connected to the connecting ring plate (8); a concrete grouting port (15) is provided in the center of the connecting ring plate (8); a steel sleeve (16) and a threaded rod (7) are provided on the connecting ring plate (8) around the concrete grouting port (15); a threaded section (17) is provided on the top of the steel pipe (11), and a tip plug (27) is provided on the bottom; the steel pipe (11) is divided into three groups, namely a first group of steel pipes (18), a second group of steel pipes (19) and a third group of steel pipes (20), the grouting holes (14) of each group of steel pipes (11) are of different heights; each group of steel pipes (11) includes two identical steel pipes (11), and the two steel pipes (11) in each group of steel pipes (11) are symmetrically inserted under the connecting ring plate (8) through a steel sleeve (16), and the top structure of the steel pipe (11) is welded with several steel bars (9); the two "J"-shaped clamps (4) fixed on the same support (2) are connected by a tension screw (25), and the "J"-shaped clamps (4) A channel steel base (23) is provided on the upper portion; the I-shaped steel column foot (22) is connected to the channel steel base (23) on the I-shaped hoop (4) through a high-strength bolt (21); the inner wall of the I-shaped hoop (4) connected to the lower surface of the support (2) is also provided with a steel pad (24); the expanded I-shaped steel column foot (26) includes an ear plate (13); a threaded rod (7) is provided on the connecting ring plate (8), and the threaded rod (7) is fixedly connected to the ear plate (13) of the expanded I-shaped steel column foot (26).

2. The complex deep foundation pit support column underpinning system according to claim 1 is characterized by: The size of the "X"-shaped steel column foot (22) matches the size of the supporting column (5), and the inner wall spacing of the "X"-shaped steel column foot (22) is greater than the length of the tension screw (25); the size of the expanded "X"-shaped steel column foot (26) matches the size of the connecting ring plate (8), and the inner wall spacing of the expanded "X"-shaped steel column foot (26) is greater than the distance between the steel sleeves (16).

3. The complex deep foundation pit support column underpinning system according to claim 1 is characterized by: The "X"-shaped hoop (4) and the connecting ring plate (8) connected to each support (2) are located on the same vertical axis, and the several segments of the supporting column (5) are located on the same vertical axis.

4. The construction method of the complex deep foundation pit support column underpinning system according to any one of claims 1 to 3, characterized in that: The following steps are involved: Step 1, positioning the replacement column: according to the position of the column to be replaced (3), a connecting ring plate (8) is set, the steel pipe (11) is passed through the steel sleeve (16) on the connecting ring plate (8) and driven to the designed position, and the soil (12) around the steel pipe (11) is excavated; the steel pipe (11) and the connecting ring plate (8) are welded into a whole through the steel bar (9); concrete is poured through the concrete grouting port (15) of the connecting ring plate (8); finally, the first group of steel pipes (18), the second group of steel pipes (19) and the third group of steel pipes (20) are sequentially subjected to post-grouting construction to form a grouting body (10); Step 3, processing the underpinning columns: Processing several sections of underpinning columns (5), setting an enlarged "J"-shaped steel column foot (26) at the bottom end of the underpinning column (5) connected to the connecting ring plate (8), setting an "J"-shaped steel column foot (22) at the top end, and setting an "J"-shaped steel column foot (22) at both ends of the remaining underpinning columns (5); Step 4: Install the "X"-shaped clamp: secure the "X"-shaped clamp (4) to both sides of each support (2); Step 5, installation of the replacement column: Install the replacement column (5), fix the "X"-shaped steel column foot (22) with the "X"-shaped hoop (4), and expand the "X"-shaped steel column foot (26) and fix it with the connecting ring plate (8); Step 6: Remove the supporting column to be replaced: Remove the supporting column to be replaced (3).

5. The construction method of the complex deep foundation pit support column underpinning system according to claim 4 is characterized in that: In step 1: the soil (12) around the steel pipe (11) is excavated to a depth of 0.8m to 1.1m.

6. The construction method of the complex deep foundation pit support column underpinning system according to claim 4 is characterized in that: In step 4, a steel backing plate (24) is provided on the inner wall of the lower surface of the I-shaped clamp (4) connecting the support (2), and the I-shaped clamp (4) is fixed to both sides of each support (2) by tensioning, and then fixed by tensioning screws (25).

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