House building foundation pit excavation construction protection structure

Abstract

The utility model relates to a house building foundation pit excavation construction protection structure, and belongs to the technical field of house building construction. Comprising a horizontal cross beam stretching across the upper portion of a foundation pit, the two ends of the horizontal cross beam are connected to a left side pile column and a right side pile column correspondingly, and multiple sets of left side connecting bases are arranged on the lower surface of the left side of the horizontal cross beam at intervals in the length direction of the horizontal cross beam; a left side soil retaining plate is mounted at the bottom end of the left side lower stand column through a left side baffle fine adjustment mechanism; a plurality of right connecting seats are arranged on the lower surface of the right side of the horizontal beam at intervals in the length direction of the horizontal beam, a right lower stand column is installed on any right connecting seat, and a right soil retaining plate is installed at the bottom end of the right lower stand column through a right baffle fine adjustment mechanism. The adjustable retaining plate has the advantages that the distance between the left retaining plate and the right retaining plate can be adjusted, the adjustable retaining plate is suitable for foundation pits with different widths, and the danger of collapse of the foundation pits is prevented to a certain extent.

Description

Technical Field

[0001] The utility model relates to a protective structure for excavation construction of a foundation pit for building construction, belonging to the technical field of building construction. Background Art

[0002] The foundation pit is a soil pit excavated at the foundation design location according to the base elevation and foundation plane dimensions. In order to protect the safety of the underground main structure construction and the surrounding environment of the foundation pit, temporary support, reinforcement, protection and groundwater control measures are required for the foundation pit. Foundation pit support is a support, reinforcement and protection measure for the side walls of the foundation pit and the surrounding environment to ensure the safety of the underground structure construction and the surrounding environment of the foundation pit.

[0003] The patent application number is CN202420177196.0, which discloses a protective device for foundation pit excavation in construction. It includes horizontal retaining plates, and each layer of horizontal retaining plates is provided with multiple plates along the front and rear directions. A column plate is provided on the inner side of the horizontal retaining plate, and an adjustable support structure is provided between two matching column plates. The front and rear ends of the horizontal retaining plate are respectively provided with dovetail-shaped connecting protrusions and connecting grooves. The column plate is provided with multiple sliding sleeves, and the sliding sleeves are provided with locking bolts. The top of the sliding sleeve is fixed with a support plate. The front and rear adjacent horizontal retaining plates of the same layer of the utility model can be connected by connecting protrusions and connecting grooves. When retaining soil, multiple horizontal retaining plates of the same layer are integrated as a whole, and the protective ability is stronger. The horizontal retaining plates are supported by support plates to prevent the horizontal retaining plates from falling downward, and the installation of the horizontal retaining plates is convenient. In addition, the support plates can adjust the height position.

[0004] Although the above patent can realize the foundation support function, the current technical considerations are not comprehensive and have the following disadvantages: in different foundation constructions, the specifications of the required foundation pits are also different, involving foundation pits of different widths. When supporting them, the existing support devices are not convenient for supporting foundation pits of different widths, and their use has certain limitations.

[0005] In order to solve one of the above problems, a protective structure for building foundation pit excavation construction is urgently needed. Utility Model Content

[0006] In view of the above deficiencies in the prior art, the technical problem to be solved by the utility model is: how to achieve adjustable spacing between the left retaining plate and the right retaining plate, which is suitable for foundation pits of different widths. The left retaining plate and the right retaining plate can be effectively abutted against the inner wall of the foundation pit, thereby preventing the risk of foundation pit collapse to a certain extent. For this purpose, a protective structure for excavation construction of foundation pit for building construction is provided.

[0007] The protective structure for construction of foundation pit excavation for housing construction described in the utility model comprises a left pile column and a right pile column on both sides of the foundation pit, and also comprises a horizontal beam spanning above the foundation pit, and the two ends of the horizontal beam are respectively connected to the left pile column and the right pile column, and is characterized in that: a plurality of groups of left connecting seats are arranged at intervals on the lower surface of the left side of the horizontal beam along its length direction, a left lower column is installed on any group of the left connecting seats, and a left retaining plate is installed on the bottom end of the left lower column through a left baffle fine-tuning mechanism; a plurality of groups of right connecting seats are arranged at intervals on the lower surface of the right side of the horizontal beam along its length direction, a right lower column is installed on any group of the right connecting seats, and a right retaining plate is installed on the bottom end of the right lower column through a right baffle fine-tuning mechanism.

[0008] By installing the left lower column on the left connecting seat at different positions, the position of the left lower column relative to the horizontal beam can be adjusted. By installing the right lower column on the right connecting seat at different positions, the position of the right lower column relative to the horizontal beam can be adjusted. The distance between the left lower column and the right lower column can be adjusted, so that the spacing between the left retaining plate and the right retaining plate can be adjusted. This is suitable for foundation pits of different widths. The left retaining plate and the right retaining plate can effectively abut against the inner wall of the foundation pit, thereby preventing the risk of foundation pit collapse to a certain extent.

[0009] At the same time, the position of the left retaining plate can also be fine-tuned by the left retaining plate fine-tuning mechanism, and the position of the right retaining plate can be fine-tuned by the right retaining plate fine-tuning mechanism, thereby ensuring the use effect of the retaining plate in the foundation pit.

[0010] Preferably, the horizontal crossbeam includes a single-sided crossbeam A and a single-sided crossbeam B which are parallel to each other, the left connecting seat and the left lower column are welded to the single-sided crossbeam A and the single-sided crossbeam B, one end of the single-sided crossbeam A and the single-sided crossbeam B are supported on the top supporting ring A on the top of the left pile column, and the left pile column is in the gap between the single-sided crossbeam A and the single-sided crossbeam B, the other end of the single-sided crossbeam A and the single-sided crossbeam B are supported on the top supporting ring B on the top of the right pile column, and the right pile column is in the gap between the single-sided crossbeam A and the single-sided crossbeam B.

[0011] Preferably, the left lower column and the right lower column are both square steel tubes, and the tops of the left lower column and the right lower column are detachably connected to the left connecting seat and the right connecting seat respectively through corresponding connecting bolts.

[0012] Preferably, the left baffle fine-tuning mechanism includes a sliding sleeve A welded to the bottom of the left lower column, an extension rod A is welded to the bottom end of the sliding sleeve A, a sliding rod A is slidably arranged in the sliding sleeve A, and the front and rear ends of the sliding rod A are respectively vertically connected with a front connecting plate A and a rear connecting plate A, and an upper screw rod A and a lower screw rod A parallel to the sliding rod A are installed between the front connecting plate A and the rear connecting plate A, and the upper screw rod A and the lower screw rod A respectively penetrate the left lower column and the extension rod A, and the sliding rod A is threadedly connected with a first abutment nut and a second nut, and the first abutment nut and the second nut are respectively clamped on both sides of the left lower column, and the lower screw rod A is threadedly connected with a third nut and a fourth nut, and the third nut and the fourth nut are respectively clamped on both sides of the extension rod A.

[0013] The upper screw rod A and the lower screw rod A cooperate with the corresponding nuts respectively to control the front connecting plate A to approach or move away from the left lower column, thereby achieving fine adjustment of the left retaining plate so that the left retaining plate is close to the inner wall of the foundation pit.

[0014] Preferably, a first oblique support is also arranged between the rear connecting plate A and the horizontal beam, and the first oblique support includes a connecting column, and the connecting column is connected to the left connecting seat in the middle of the horizontal beam, and the bottom end of the connecting column is hinged with an internal threaded tube A, and the back side of the rear connecting plate A is hinged with an internal threaded tube B, and the internal threaded tube A and the internal threaded tube B are connected by a screw, and a handle is installed in the middle of the screw. The screw is rotated by the handle to adjust the depth of the screw in the internal threaded tube A and the internal threaded tube B, thereby adjusting the full length of the first oblique support, which can effectively support the rear connecting plate A.

[0015] Preferably, the right baffle fine-tuning mechanism includes a sliding sleeve B welded to the bottom of the right lower column, an extension rod B is welded to the bottom end of the sliding sleeve B, a sliding rod B is slidably arranged in the sliding sleeve B, and the front and rear ends of the sliding rod B are respectively vertically connected with a front connecting plate B and a rear connecting plate B, and an upper screw rod B and a lower screw rod B parallel to the sliding rod B are installed between the front connecting plate B and the rear connecting plate B, and the upper screw rod B and the lower screw rod B respectively penetrate the right lower column and the extension rod B, and the sliding rod B is threadedly connected with a fifth abutment nut and a sixth nut, and the fifth abutment nut and the sixth nut are respectively clamped on both sides of the right lower column 9, and the lower screw rod B is threadedly connected with a seventh nut and an eighth nut, and the seventh nut and the eighth nut are respectively clamped on both sides of the extension rod B.

[0016] Preferably, a second oblique support is further provided between the rear connecting plate B and the horizontal cross beam, and the second oblique support has the same structure as the first oblique support.

[0017] Preferably, the left retaining plate is connected to the front connecting plate A through multiple groups of high-strength bolts A, and the right retaining plate is connected to the front connecting plate B through multiple groups of high-strength bolts B.

[0018] Compared with the prior art, the utility model has the following beneficial effects:

[0019] The protective structure for excavation construction of a foundation pit for building construction described in the utility model has an adjustable distance between the left lower column and the right lower column, so that the spacing between the left retaining plate and the right retaining plate can be adjusted, and is suitable for foundation pits of different widths. The left retaining plate and the right retaining plate can effectively abut against the inner wall of the foundation pit, thereby preventing the risk of collapse of the foundation pit to a certain extent.

[0020] The protective structure for building foundation pit excavation construction described in the utility model can fine-tune the position of the left retaining plate through the left retaining plate fine-tuning mechanism, and the position of the right retaining plate through the right retaining plate fine-tune the mechanism, thereby ensuring the use effect of the retaining plate in the foundation pit.

[0021] In the protective structure for excavation construction of a foundation pit for building construction described in the utility model, a first oblique support is further provided between the rear connecting plate A and the horizontal beam to enhance the stability of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0023] Figure 1 It is a schematic diagram of the structure of the utility model;

[0024] Figure 2 It is a partial diagram of the utility model;

[0025] Figure 3 It is a top view of the top support ring A.

[0026] In the figure: 1, left pile 1.1, top supporting ring A 2, right pile 2.1, top supporting ring B 3, horizontal beam 3.1, single-side beam A 3.2, single-side beam B 4, left connecting seat 5, left lower column 6, left baffle fine-adjustment mechanism 6.1, sliding sleeve A 6.2, extension rod A 6.3, sliding rod A 6.4, front connecting plate A 6.5, rear connecting plate A 6.6, upper screw rod A 6.7, lower screw rod A 6.8, first abutment nut 7, left retaining plate 8, right connecting seat 9, right lower column 10, right baffle fine-adjustment mechanism 11, right retaining plate 12, first oblique support 12.1, internal threaded tube A 12.2, screw rod 12.3, internal threaded tube B 12.4, handle 12.5, connecting column 13, second oblique support. DETAILED DESCRIPTION

[0027] The utility model is further described below in conjunction with the accompanying drawings: The utility model is further illustrated below through specific embodiments, but is not intended to limit the utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the invention should be included in the protection scope of the utility model.

[0028] Embodiment 1, as Figure 1-2 As shown, a protective structure for excavation construction of a foundation pit for building construction comprises a left pile column 1 and a right pile column 2 located on both sides of the foundation pit, and also comprises a horizontal beam 3 spanning above the foundation pit, wherein the two ends of the horizontal beam 3 are respectively connected to the left pile column 1 and the right pile column 2, and a plurality of groups of left connecting seats 4 are arranged at intervals on the lower surface of the left side of the horizontal beam 3 along its length direction, and a left lower column 5 is installed on any group of the left connecting seats 4, and a left retaining plate 7 is installed on the bottom end of the left lower column 5 through a left baffle fine-tuning mechanism 6; a plurality of groups of right connecting seats 8 are arranged at intervals on the lower surface of the right side of the horizontal beam 3 along its length direction, and a right lower column 9 is installed on any group of the right connecting seats 8, and a right retaining plate 11 is installed on the bottom end of the right lower column 9 through a right baffle fine-tuning mechanism 10. By installing the left lower column 5 on the left connecting seat 4 at different positions, the position of the left lower column 5 relative to the horizontal beam 3 can be adjusted. By installing the right lower column 9 on the right connecting seat 8 at different positions, the position of the right lower column 9 relative to the horizontal beam 3 can be adjusted. The distance between the left lower column 5 and the right lower column 9 can be adjusted, so that the spacing between the left retaining plate 7 and the right retaining plate 11 can be adjusted. It is suitable for foundation pits of different widths. The left retaining plate 7 and the right retaining plate 11 can effectively abut against the inner wall of the foundation pit, thereby preventing the danger of collapse of the foundation pit to a certain extent.

[0029] At the same time, the position of the left retaining plate 7 can also be fine-tuned by the left retaining plate fine-tuning mechanism 6, and the position of the right retaining plate 11 can be fine-tuned by the right retaining plate fine-tuning mechanism 10, thereby ensuring the use effect of the retaining plate in the foundation pit.

[0030] Embodiment 2, as Figure 1-3As shown, a protective structure for excavation construction of a foundation pit for building construction comprises a left pile column 1 and a right pile column 2 located on both sides of the foundation pit, and also comprises a horizontal beam 3 spanning above the foundation pit, wherein the two ends of the horizontal beam 3 are respectively connected to the left pile column 1 and the right pile column 2, and a plurality of groups of left connecting seats 4 are arranged at intervals on the lower surface of the left side of the horizontal beam 3 along its length direction, and a left lower column 5 is installed on any group of the left connecting seats 4, and a left retaining plate 7 is installed on the bottom end of the left lower column 5 through a left baffle fine-tuning mechanism 6; a plurality of groups of right connecting seats 8 are arranged at intervals on the lower surface of the right side of the horizontal beam 3 along its length direction, and a right lower column 9 is installed on any group of the right connecting seats 8, and a right retaining plate 11 is installed on the bottom end of the right lower column 9 through a right baffle fine-tuning mechanism 10.

[0031] Furthermore, the horizontal beam 3 includes a single-sided beam A3.1 and a single-sided beam B3.2 which are parallel to each other, the left connecting seat 4 and the left lower column 5 are welded to the single-sided beam A3.1 and the single-sided beam B3.2, one end of the single-sided beam A3.1 and the single-sided beam B3.2 are supported on the top supporting ring A1.1 at the top of the left pile column 1, and the left pile column 1 is in the gap between the single-sided beam A3.1 and the single-sided beam B3.2, the other end of the single-sided beam A3.1 and the single-sided beam B3.2 are supported on the top supporting ring B2.1 at the top of the right pile column 2, and the right pile column 2 is in the gap between the single-sided beam A3.1 and the single-sided beam B3.2.

[0032] Furthermore, the left lower column 5 and the right lower column 9 are both square steel pipes, and the tops of the left lower column 5 and the right lower column 9 are detachably connected to the left connecting seat 4 and the right connecting seat 8 respectively through corresponding connecting bolts.

[0033] Furthermore, the left baffle fine-tuning mechanism 6 includes a sliding sleeve A6.1 welded to the bottom of the left lower column 5, an extension rod A6.2 is welded to the bottom end of the sliding sleeve A6.1, a sliding rod A6.3 is slidably arranged in the sliding sleeve A6.1, and the front and rear ends of the sliding rod A6.3 are respectively vertically connected to a front connecting plate A6.4 and a rear connecting plate A6.5, and an upper screw rod A6.3 parallel to the sliding rod A6.3 is installed between the front connecting plate A6.4 and the rear connecting plate A6.5. 6.6, lower screw rod A6.7, the upper screw rod A6.6 and the lower screw rod A6.7 respectively penetrate the left lower column 5 and the extension rod A6.2, the sliding rod A6.3 is threadedly connected with a first abutment nut 6.8 and a second nut, the first abutment nut 6.8 and the second nut are respectively clamped on both sides of the left lower column 5, the lower screw rod A6.7 is threadedly connected with a third nut and a fourth nut, the third nut and the fourth nut are respectively clamped on both sides of the extension rod A6.2.

[0034] The upper screw rod A6.6 and the lower screw rod A6.7 cooperate with the corresponding nuts respectively to control the front connecting plate A6.4 to approach or move away from the left lower column 5, so as to achieve fine adjustment of the left retaining plate 7 so that the left retaining plate 7 is close to the inner wall of the foundation pit.

[0035] Furthermore, a first oblique support 12 is also arranged between the rear connecting plate A6.5 and the horizontal beam 3, and the first oblique support includes a connecting column 12.5, and the connecting column 12.5 is connected to the left connecting seat 4 in the middle of the horizontal beam 3, and the bottom end of the connecting column 12.5 is hinged with an internal threaded tube A12.1, and the back side of the rear connecting plate A6.5 is hinged with an internal threaded tube B12.3, and the internal threaded tube A12.1 and the internal threaded tube B12.3 are connected by a screw 12.2, and a handle 12.4 is installed in the middle of the screw 12.2. The screw 12.2 is rotated by the handle 12.4 to adjust the depth of the screw 12.2 in the internal threaded tube A12.1 and the internal threaded tube B12.3, thereby adjusting the full length of the first oblique support 12, which can effectively support the rear connecting plate A6.5.

[0036] Furthermore, the right baffle fine-tuning mechanism 10 includes a sliding sleeve B welded to the bottom of the right lower column 9, an extension rod B is welded to the bottom end of the sliding sleeve B, a sliding rod B is slidably arranged in the sliding sleeve B, and the front and rear ends of the sliding rod B are respectively vertically connected with a front connecting plate B and a rear connecting plate B, and an upper screw rod B and a lower screw rod B parallel to the sliding rod B are installed between the front connecting plate B and the rear connecting plate B, and the upper screw rod B and the lower screw rod B respectively penetrate the right lower column 9 and the extension rod B, and the sliding rod B is threadedly connected with a fifth abutment nut and a sixth nut, and the fifth abutment nut and the sixth nut are respectively clamped on both sides of the right lower column 9, and the lower screw rod B is threadedly connected with a seventh nut and an eighth nut, and the seventh nut and the eighth nut are respectively clamped on both sides of the extension rod B.

[0037] Furthermore, a second oblique support 13 is provided between the rear connecting plate B and the horizontal cross beam 3 , and the second oblique support has the same structure as the first oblique support.

[0038] Furthermore, the left retaining plate 7 is connected to the front connecting plate A6.4 through multiple groups of high-strength bolts A, and the right retaining plate 11 is connected to the front connecting plate B through multiple groups of high-strength bolts B.

[0039] The protective structure for excavation construction of a foundation pit for building construction described in the utility model has an adjustable distance between the left lower column and the right lower column, so that the spacing between the left retaining plate and the right retaining plate can be adjusted, and is suitable for foundation pits of different widths. The left retaining plate and the right retaining plate can effectively abut against the inner wall of the foundation pit, thereby preventing the risk of collapse of the foundation pit to a certain extent.

[0040] The protective structure for building foundation pit excavation construction described in the utility model can fine-tune the position of the left retaining plate through the left retaining plate fine-tuning mechanism, and the position of the right retaining plate through the right retaining plate fine-tune the mechanism, thereby ensuring the use effect of the retaining plate in the foundation pit.

[0041] In the protective structure for excavation construction of a foundation pit for building construction described in the utility model, a first oblique support is further provided between the rear connecting plate A and the horizontal beam to enhance the stability of the structure.

[0042] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection claimed by the present utility model is defined by the attached claims and their equivalents.

[0043] The matters not described in detail in the present invention are all known technologies to those skilled in the art.

Claims

1. A protective structure for excavation of a foundation pit for a building, comprising a left pile and a right pile on both sides of the foundation pit, and a horizontal beam spanning the top of the foundation pit, wherein the two ends of the horizontal beam are respectively connected to the left pile and the right pile, and characterized in that: A plurality of groups of left-side connecting seats are arranged at intervals on the lower surface of the left side of the horizontal beam along its length direction, and a left-side lower column is installed on any group of the left-side connecting seats, and a left-side earth retaining plate is installed on the bottom end of the left-side lower column through a left-side baffle fine-adjustment mechanism; a plurality of groups of right-side connecting seats are arranged at intervals on the lower surface of the right side of the horizontal beam along its length direction, and a right-side lower column is installed on any group of the right-side connecting seats, and a right-side earth retaining plate is installed on the bottom end of the right-side lower column through a right-side baffle fine-adjustment mechanism.

2. The protective structure for building foundation pit excavation construction according to claim 1 is characterized in that: The horizontal crossbeam includes a single-sided crossbeam A and a single-sided crossbeam B which are parallel to each other. The left connecting seat and the left lower column are welded to the single-sided crossbeam A and the single-sided crossbeam B. One end of the single-sided crossbeam A and the single-sided crossbeam B are supported on the top supporting ring A on the top of the left pile column, and the left pile column is in the gap between the single-sided crossbeam A and the single-sided crossbeam B. The other ends of the single-sided crossbeam A and the single-sided crossbeam B are supported on the top supporting ring B on the top of the right pile column, and the right pile column is in the gap between the single-sided crossbeam A and the single-sided crossbeam B.

3. The protective structure for building foundation pit excavation construction according to claim 2 is characterized in that: The left lower column and the right lower column are both square steel pipes, and the tops of the left lower column and the right lower column are detachably connected to the left connecting seat and the right connecting seat respectively through corresponding connecting bolts.

4. The protective structure for building foundation pit excavation construction according to claim 3 is characterized in that: The left baffle fine-tuning mechanism includes a sliding sleeve A welded to the bottom of the left lower column, an extension rod A is welded to the bottom end of the sliding sleeve A, a sliding sleeve A is slidably arranged with a sliding rod A, and the front and rear ends of the sliding rod A are respectively vertically connected with a front connecting plate A and a rear connecting plate A, and an upper screw rod A and a lower screw rod A parallel to the sliding rod A are installed between the front connecting plate A and the rear connecting plate A, and the upper screw rod A and the lower screw rod A respectively penetrate the left lower column and the extension rod A, and the sliding rod A is threadedly connected with a first abutment nut and a second nut, and the first abutment nut and the second nut are respectively clamped on both sides of the left lower column, and the lower screw rod A is threadedly connected with a third nut and a fourth nut, and the third nut and the fourth nut are respectively clamped on both sides of the extension rod A.

5. The protective structure for building foundation pit excavation construction according to claim 4 is characterized in that: A first oblique support is also arranged between the rear connecting plate A and the horizontal beam, and the first oblique support includes a connecting column, which is connected to the left connecting seat in the middle of the horizontal beam, and the bottom end of the connecting column is hinged with an internal threaded tube A, and the back side of the rear connecting plate A is hinged with an internal threaded tube B, and the internal threaded tube A and the internal threaded tube B are connected by a screw, and a handle is installed in the middle of the screw.

6. The protective structure for building foundation pit excavation construction according to claim 5 is characterized in that: The right baffle fine-tuning mechanism includes a sliding sleeve B welded to the bottom of the right lower column, an extension rod B is welded to the bottom of the sliding sleeve B, a sliding sleeve B is slidably arranged with a sliding sleeve B, and the front and rear ends of the sliding rod B are respectively vertically connected with a front connecting plate B and a rear connecting plate B, and an upper screw rod B and a lower screw rod B parallel to the sliding rod B are installed between the front connecting plate B and the rear connecting plate B, and the upper screw rod B and the lower screw rod B respectively penetrate the right lower column and the extension rod B, and the sliding rod B is threadedly connected with a fifth abutment nut and a sixth nut, and the fifth abutment nut and the sixth nut are respectively clamped on both sides of the right lower column, and the lower screw rod B is threadedly connected with a seventh nut and an eighth nut, and the seventh nut and the eighth nut are respectively clamped on both sides of the extension rod B.

7. The protective structure for building foundation pit excavation construction according to claim 6 is characterized in that: A second oblique support is further provided between the rear connecting plate B and the horizontal cross beam, and the second oblique support has the same structure as the first oblique support.

8. The protective structure for building foundation pit excavation construction according to claim 7 is characterized in that: The left retaining plate is connected to the front connecting plate A through multiple groups of high-strength bolts A, and the right retaining plate is connected to the front connecting plate B through multiple groups of high-strength bolts B.

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