Adjustable edge support structure for soft soil foundation pit maintenance

Abstract

The application discloses an adjustable side support structure for soft soil foundation pit maintenance, which comprises multiple groups of support structures arranged along the periphery of the foundation pit, and the support structures can be vertically inserted and arranged along the edge of the foundation pit in the up-down direction. The application is aimed at soft soil foundation pit maintenance, and replaces the support mode of fixing the structure after the formation of the foundation pit into the "dynamic support" mode of supporting while excavating. The support is gradually performed by adopting the mode of multiple groups of adjustable arrangements along the periphery and the mode of splicing and piling from top to bottom. The parameters of the support structure are adjusted according to the actual excavation needs, the gradually formed foundation pit is comprehensively supported, and the soil deformation is prevented. Compared with the conventional fixed plate-shaped support structure, the support structure is convenient for adjusting the support height, width and angle, is suitable for supporting foundation pits of different shapes, effectively improves the construction flexibility, and is not prone to the condition that a single support pile is inclined by adopting the combined anchoring support mode.

Description

Technical Field

[0001] This invention relates to the field of foundation pit support and maintenance technology, and more specifically, to an adjustable edge support structure for the maintenance of soft soil foundation pits. Background Technology

[0002] An excavation pit is a pit dug at the foundation design location according to the base elevation and foundation plane dimensions. Soil in soft soil areas has characteristics such as low shear strength, high compressibility, and poor permeability. During the excavation of the excavation pit, as the depth increases, the soil's own supporting capacity gradually weakens. If support is not provided in time, the soil may collapse because it cannot bear its own weight and external loads.

[0003] A search revealed a patent publication number CN116446412A that discloses a foundation pit support structure in soft soil areas. The structure involves driving anchors into the soil by hammering cast-in-place piles, then pouring concrete into the piles. The concrete pushes the anchor claws out of the anchors and causes them to unfold. The concrete flows out from the first grout outlet and mixes with the soft soil to solidify, thus expanding the range and volume of concrete-soil cohesion. However, traditional foundation pit excavation involves digging downwards in sections and layers, while this support structure has side supports and bottom supports, requiring the support structure to be lowered after the foundation pit excavation is completed.

[0004] Furthermore, when deep foundation pits are excavated in soft soil areas, when the depth of the foundation pit reaches a certain level, the soil on the pit wall will be squeezed into the pit under the action of lateral pressure, causing the foundation pit to deform or even collapse. In addition, for some foundation pits with complex shapes (such as circular, elliptical, etc.), traditional plate-shaped support structures may be difficult to adapt to their shape changes.

[0005] To address the aforementioned issues, an adjustable edge support structure for soft soil foundation pit maintenance is proposed. This adjustable edge support structure can be flexibly adjusted according to the shape of the foundation pit, achieving effective support for foundation pits with complex shapes. Summary of the Invention

[0006] The purpose of this invention is to solve existing practical problems and provide an adjustable edge support structure for the maintenance of soft soil foundation pits compared with existing technologies.

[0007] The objective of this invention can be achieved through the following technical solution: an adjustable edge support structure for the maintenance of soft soil foundation pits, comprising multiple sets of support structures arranged along the perimeter of the foundation pit, wherein the support structures can be vertically inserted and arranged along the edge of the foundation pit, the support structure comprising hollow anchors and multiple support piles located outside the hollow anchors and arranged along the inner wall of the perimeter of the foundation pit, adjacent support piles being connected by left and right rotation through an adjustment component, the support pile located in the middle being movably connected to the hollow anchors through multiple inclined abutments set upwards towards one end of the hollow anchors, and an anchoring component for pushing the inclined abutments downwards to press against the support piles between the hollow anchors and the support piles;

[0008] The support pile has grouting grooves with openings at the top and bottom. The lower end of the support pile has a pointed part that communicates with the grouting grooves. The upper end of the support pile has a mating part that matches the pointed part. Both the pointed part and the mating part have multiple external injection holes on their outer walls. The upper end of the hollow anchor has a mating sleeve that matches its bottom end.

[0009] Furthermore, the hollow anchor is also provided with an anchoring column that penetrates its bottom and is driven into the foundation pit. The length of the anchoring column is greater than the length of a single hollow anchor.

[0010] Furthermore, the adjustment assembly between two adjacent support piles is provided in multiple sets, including a steel ring fixedly sleeved on the outer wall of the support pile, and the steel rings arranged on the left and right sides are movably connected by a movable buckle. The outer wall of the support pile is provided with a movable groove located inside the steel ring for adjusting the movable buckle, so as to realize the rotational connection between two adjacent support piles, thereby adapting to the perimeter distribution of different foundation pits.

[0011] Furthermore, the hollow anchor has a groove on its end wall for sliding the inclined abutment up and down. The lower end of the inclined abutment is movably connected to the bottom of the groove through an elastic plate. The other end of the inclined abutment is hinged to the outer wall of the support pile. Multiple inclined abutments have side openings and anchoring grooves that are compatible with the anchoring assembly.

[0012] Furthermore, the anchoring assembly includes an anchoring rod sleeved within multiple upper and lower anchoring grooves, and multiple abutment plates corresponding to the positions of the anchoring grooves are fixedly sleeved on the anchoring rod.

[0013] Furthermore, a cast-in-place inner column extending into the tip is placed inside the support pile, and the bottom end of the cast-in-place inner column is provided with an inner grouting hole that communicates with the outer grouting hole on the tip.

[0014] Furthermore, the top of the support structure is provided with a grouting sealing structure, which includes a sealing column that is connected to the uppermost connecting sleeve, and multiple grouting cones corresponding to the uppermost connecting part are provided on the outside of the sealing column.

[0015] Furthermore, the grouting cone located in the middle is fixedly connected to the sealing column by a connector, and adjacent two are also connected by an adjustment component. The grouting cone is provided with a grouting hole that communicates with the grouting groove.

[0016] Compared with the prior art, the advantages of this invention are:

[0017] 1. This solution is designed for the maintenance of soft soil foundation pits. It replaces the conventional support mode of constructing fixed structures after the foundation pit has formed with a "dynamic support" mode that supports the pit while it is being excavated. According to the excavation progress, multiple adjustable piles are arranged along the perimeter and spliced ​​from top to bottom to gradually provide support. The parameters of the support structure can be adjusted in a timely manner according to the actual excavation needs, providing comprehensive support for the gradually forming foundation pit and preventing soil deformation. Compared with conventional fixed support structures, this support structure is easier to adjust in terms of support height, width and angle, making it convenient to adapt to foundation pits of different shapes and sizes, and effectively improving construction flexibility.

[0018] 2. The support structure consists of a single hollow anchor and multiple flexibly hinged support piles. During construction, compared to driving multiple individual piles down one by one, the adjustable combined support structure facilitates the overall arrangement of multiple support structures along the perimeter of the foundation pit, effectively improving construction efficiency. In addition, the inner sides of multiple support piles are equipped with hollow anchors that are also anchored in the foundation pit, forming an internally dispersed support and an externally tightly arranged support pattern. With the addition of anchoring components between the two, the inner and outer support points form mutual support and restraint, further improving the stability of the support structure. Attached Figure Description

[0019] Figure 1 This is a structural schematic diagram of the present invention during the support process of the foundation pit;

[0020] Figure 2 This is a schematic diagram of the structure at the junction of the support structure and the anchor column of the present invention;

[0021] Figure 3 This is a schematic diagram of the support structure of the present invention;

[0022] Figure 4 This is a partially exploded view of the support structure of the present invention;

[0023] Figure 5 This is a schematic diagram of the structure when the upper and lower support piles of the present invention are spliced ​​together.

[0024] Figure 6 This is an enlarged sectional view of the upper and lower spliced ​​support piles of the present invention;

[0025] Figure 7This is a schematic diagram of the anchoring assembly of the present invention;

[0026] Figure 8 This is a schematic diagram of the structure of the present invention when using anchoring components to reinforce the supporting structure;

[0027] Figure 9 This is a schematic diagram of the grouting and sealing structure of the present invention;

[0028] Figure 10 This is a schematic diagram of the structure of the present invention during grouting of the supporting structure.

[0029] Explanation of the labels in the diagram:

[0030] 1. Excavation pit; 2. Hollow anchor; 201. Butt sleeve; 3. Support pile; 301. Tip; 302. Butt joint; 303. External grouting hole; 4. Reinforcing ring; 5. Loose buckle; 6. Inclined abutment; 7. Anchor column; 8. Cast-in-place inner column; 9. Anchor rod; 10. Abutment plate; 11. Sealing column; 12. Grouting cone; 121. Grouting hole. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0032] Example 1: In soft soil construction environments, when the foundation pit reaches a certain depth, the soil on the pit wall will be squeezed inward under lateral pressure. If conventional support is provided after the foundation pit is formed, it is difficult to ensure that the foundation pit will not deform or collapse during excavation. In addition, for some foundation pits with complex shapes (such as circular, elliptical, etc.), traditional plate-like support structures may be difficult to adapt to their shape changes. The following technical solution is proposed:

[0033] This invention discloses an adjustable edge support structure for the maintenance of soft soil foundation pits. Please refer to [link / reference]. Figures 1-4 This includes multiple sets of support structures arranged along the periphery of the foundation pit 1, and these multiple sets of support structures can be inserted and arranged vertically along the edge of the foundation pit 1.

[0034] The support structure includes hollow anchors 2 and multiple support piles 3 arranged on the outer side of the hollow anchors 2 and along the inner wall of the perimeter of the foundation pit 1. Adjacent support piles 3 are connected by adjusting components that rotate left and right. Multiple sets of adjusting components are provided between adjacent support piles 3, including steel rings 4 fixedly sleeved on the outer wall of the support pile 3. Adjacent steel rings 4 are movably connected by movable buckles 5. The outer wall of the support pile 3 is provided with movable grooves located inside the steel rings 4 for adjusting the movable buckles 5, so as to realize the rotatable connection between adjacent support piles 3, thereby adapting to different perimeter shapes of foundation pits.

[0035] The support pile 3 located in the middle is connected to the hollow anchor 2 by multiple inclined abutments 6 that are inclined upward towards one end of the hollow anchor 2. The hollow anchor 2 and the multiple support piles 3 are connected in a movable manner. A set of support structures is formed by the combination of a single hollow anchor 2 and multiple support piles 3. The hollow anchor 2 is also provided with an anchor column 7 that penetrates its bottom and is driven into the foundation pit 1. The length of the anchor column 7 is greater than the length of a single hollow anchor 2.

[0036] During construction, a preliminary foundation pit of a certain depth is first excavated at the target site according to the construction drawings. The pile positions of the support structure are marked along the perimeter of the foundation pit. A drilling rig is used to drill down to the depth of one set of support structures. Multiple sets of support structures are arranged according to the pile positions. The adjustable support piles 3 are arranged to fit against the inner wall of the perimeter of the foundation pit. The hollow anchors 2 are located inside the support piles 3. The pile driving around the perimeter of the foundation pit is completed in one go. Then, multiple anchor columns 7 are hoisted inside multiple hollow anchors 2 and piles are driven down further. At this time, the preliminary support structure is formed. The setting of anchor columns 7 is conducive to improving the anchoring effect of the support structure.

[0037] During the subsequent layer-by-layer support process, the support structure is spliced ​​upward according to the excavation progress and excavation depth. Note that after the first layer of support is completed, the upper part of the support structure is exposed at the top of the foundation pit, which facilitates the splicing and sinking of the upper support structure. The upper support structure is driven downward using on-site pile driving equipment, and the hollow anchor 2 sinks along the pile driving position of the anchor column 7 to improve the accuracy of the anchoring position.

[0038] The upper and lower supporting structures are stably sunk under impact, ensuring that the upper supporting structure is exposed on the inner wall of the formed pit perimeter. Compared with the sequential lowering of multiple single piles, the adjustable combined supporting structure facilitates the overall arrangement of multiple supporting structures along the perimeter of the pit, effectively improving construction efficiency. In addition, the inner side of multiple support piles 3 is equipped with hollow anchors 2 that are also anchored in the pit 1, forming an internally dispersed support and an externally tightly arranged support pattern.

[0039] Please see Figures 7-8An anchoring assembly is provided between the hollow anchor 2 and the support pile 3 for pushing the inclined abutment 6 downward to abut the support pile 3. A sliding groove is provided on the end wall of the hollow anchor 2 for the inclined abutment 6 to slide up and down. The lower end of the inclined abutment 6 is movably connected to the bottom end of the sliding groove through an elastic plate. The other end of the inclined abutment 6 is hinged to the outer wall of the support pile 3. An anchoring groove with side openings and adapted to the anchoring assembly is provided on the upper and lower inclined abutments 6. The anchoring assembly includes an anchoring rod 9 sleeved in the upper and lower anchoring grooves. Multiple abutment plates 10 corresponding to the positions of the anchoring grooves are fixedly sleeved on the anchoring rod 9.

[0040] After construction is completed, multiple sets of support structures are distributed around the perimeter and vertically around the foundation pit. At this time, anchoring components are added at the multiple inclined abutments 6 set vertically. Anchor rods 9 pass through the anchoring grooves on the inclined abutments 6, and multiple abutment plates 10 correspond one by one to the anchoring grooves. After the two are movably connected, the anchor rods 9 are hammered downwards, causing the multiple abutment plates 10 to press the inclined abutments 6 downwards. During the downward pressing of the inclined abutments 6, they play a pushing and abutting role on the outer support piles 3, which not only improves the stability between the support piles 3 and the hollow anchors 2, but also improves the support stability of the support piles 3 on the inner wall of the foundation pit. In addition, the use of combined anchoring support method further improves the support strength and makes it less likely for a single support pile to tilt.

[0041] The conventional support mode of constructing fixed structures after the foundation pit is formed is replaced by a "dynamic support" mode that supports while excavating. According to the excavation progress, multiple adjustable piles are arranged along the perimeter and spliced ​​from top to bottom to gradually carry out support. The parameters and forms of the support structure can be adjusted in a timely manner according to the actual excavation needs. It does not require a large amount of material and equipment resources to be invested at once, but supports are carried out gradually according to the excavation progress, reducing the backlog of materials and the idle time of equipment.

[0042] Furthermore, if the local soil layer is found to be worse than the survey report during the excavation process, the number of upper and lower splices of the support structure can be increased in time, and the support structure can be extended deeper into the soft soil, that is, the support depth can be adjusted. Multiple support piles are hinged about 3 times to facilitate the support of the perimeter of the foundation pit with different shapes and sizes, effectively improving the construction flexibility. In addition, excavation and support can be carried out simultaneously with earthwork excavation. By reasonably arranging the construction sequence and time, the construction period of the entire project can be effectively shortened.

[0043] Example 2, based on Example 1, further supplements the description of the support structure, as follows:

[0044] Please see Figures 4-6The support pile 3 has grouting grooves with openings at the top and bottom. The lower end of the support pile 3 has a pointed part 301 that communicates with the grouting grooves. The upper end of the support pile 3 has a connecting part 302 that matches the pointed part 301. Both the pointed part 301 and the connecting part 302 have multiple external injection holes 303 on their outer walls. The upper end of the hollow anchor 2 has a connecting sleeve 201 that matches its bottom end.

[0045] Inside the support pile 3, a cast inner column 8 extending into the tip 301 is placed. The bottom of the cast inner column 8 is provided with an inner grouting hole that communicates with the outer grouting hole 303 on the tip 301. The connecting sleeve 201 provided on the tip 301, the connecting part 302, and the hollow anchor 2 in the vertical direction of the support pile 3 facilitates the splicing of the upper support structure onto the lower support structure. The bottom of the tip 301 at the bottom is in a closed state, which is conducive to the sinking of the pile. The bottom of the multiple tips 301 above are opened, and the upper and lower connections are achieved through the cast inner column 8 after the multiple support piles 3 are spliced.

[0046] Please see Figure 9 , Figure 10 The top of the support structure is provided with a grouting and sealing structure. The grouting and sealing structure includes a sealing column 11 that is connected to the uppermost connecting sleeve 201. The outer side of the sealing column 11 is provided with a plurality of grouting cones 12 corresponding to the uppermost connecting part 302. The grouting cone 12 located in the middle is fixedly connected to the sealing column 11 by a connector. Adjacent two 112 are also connected by an adjustment component. The grouting cone 12 is provided with a grouting hole 121 that is connected to the grouting groove.

[0047] After the overall support work is completed, the grouting sealing structure is hoisted onto the support structure. The multiple grouting cones 12 on the grouting sealing structure are also connected by hinges. This is suitable for the support piles 3 arranged according to different perimeter shapes of the foundation pit. After the grouting sealing structure is lowered, grouting is performed into the support piles 3 using multiple grouting holes 121. The concrete slurry is injected downward into the support piles 3 and overflows outward through the splicing part of the upper and lower support piles 3 and the outer grouting hole 303 of the lowest tip 301. After the slurry overflows from the outer grouting hole 303, it reinforces the splicing part of the upper and lower support piles 3.

[0048] In addition, the overflowing slurry blends with the inner wall of the foundation pit, further improving the support effect of the support structure on the foundation pit. The inner column 8 is set inside the support pile 3. When the support structure is recycled, after removing the concrete material of the upper and lower parts of the support pile 3, the inner column 8 can be disassembled outward, which makes it convenient to knock off the concrete material of the inner wall of the support pile 3 for reuse.

[0049] In summary, this approach addresses the maintenance of soft soil foundation pits by replacing the conventional support model of constructing fixed structures after the pit has formed with a "dynamic support" model that involves simultaneous excavation and support. Based on the excavation progress, multiple adjustable piles are arranged along the perimeter and installed from top to bottom for progressive support. This allows for timely adjustment of the support structure parameters and form according to actual excavation needs. Specifically:

[0050] Each support structure consists of a single hollow anchor 2 and multiple flexibly hinged support piles 3. The flexibly adjustable support piles 3 can be arranged to fit the inner wall of the foundation pit perimeter. The hollow anchor 2 is dispersedly anchored to the inner side of the support piles 3, forming an internally dispersed support and an externally tightly arranged support mode, which provides comprehensive support for the gradually forming foundation pit, prevents soil deformation, and compared with conventional fixed support structures, this support structure is easy to adjust the support height, width and angle, and can easily adapt to foundation pit support of different shapes and sizes, effectively improving construction flexibility.

[0051] The above description is merely a preferred embodiment of the present invention; however, the scope of protection of the present invention is not limited thereto; any equivalent substitutions or modifications made by those skilled in the art within the technical scope disclosed in the present invention, based on the technical solution and its improved concept, should be covered within the scope of protection of the present invention.

Claims

1. An adjustable edge support structure for soft soil excavation maintenance, characterized in that: The structure includes multiple sets of support structures arranged along the periphery of the pit (1), and the support structures can be inserted and arranged vertically along the edge of the pit (1). The support structure includes hollow anchors (2) and multiple support piles (3) located outside the hollow anchors (2) and arranged along the inner wall of the periphery of the pit (1). Adjacent support piles (3) are connected by adjusting components to rotate left and right. The support pile (3) located in the middle is connected to the hollow anchors (2) by multiple inclined abutments (6) set upwards towards one end of the hollow anchors (2). An anchoring component is provided between the hollow anchors (2) and the support piles (3) for pushing the inclined abutments (6) downwards to press against the support piles (3). Multiple sets of adjustment components are provided between two adjacent support piles (3), including steel rings (4) fixedly sleeved on the outer wall of the support pile (3), and the steel rings (4) arranged on the left and right sides are movably connected by a snap ring (5); The hollow anchor (2) has a groove on its end wall for the inclined abutment (6) to slide up and down. The lower end of the inclined abutment (6) is movably connected to the bottom end of the groove through an elastic sheet. The other end of the inclined abutment (6) is hinged to the outer wall of the support pile (3). The upper and lower inclined abutments (6) are all provided with side openings and anchor grooves that are compatible with the anchoring components. The anchoring assembly includes an anchor rod (9) sleeved in multiple upper and lower anchoring grooves, and multiple abutment plates (10) corresponding to the positions of the anchoring grooves are fixedly sleeved on the anchor rod (9). The support pile (3) has a grouting groove with openings at the top and bottom. The lower end of the support pile (3) has a pointed part (301) that communicates with the grouting groove. The upper end of the support pile (3) has a connecting part (302) that matches the pointed part (301). The outer walls of the pointed part (301) and the connecting part (302) both have multiple external injection holes (303). The upper end of the hollow anchor (2) has a connecting sleeve (201) that matches its bottom end.

2. The adjustable edge support structure for soft soil pit maintenance according to claim 1, wherein: The hollow anchor (2) is also provided with an anchor column (7) that penetrates its bottom and is driven into the foundation pit (1). The length of the anchor column (7) is greater than the length of a single hollow anchor (2).

3. The adjustable edge support structure for soft soil pit maintenance according to claim 1, wherein: The support pile (3) has a cast inner column (8) that extends into the tip (301) through it. The bottom end of the cast inner column (8) is provided with an inner grouting hole that communicates with the outer grouting hole (303) on the tip (301).

4. The adjustable edge support structure for soft soil pit maintenance according to claim 1, wherein: The top of the support structure is provided with a grouting sealing structure, which includes a sealing column (11) connected to the uppermost connecting sleeve (201), and a plurality of grouting cones (12) corresponding to the uppermost connecting part (302) are provided on the outside of the sealing column (11).

5. The adjustable edge support structure for soft soil pit maintenance according to claim 4, wherein: The grouting cone (12) located in the middle is fixedly connected to the sealing column (11) by a connector. The two adjacent (112) are also connected by an adjustment component. The grouting cone (12) is provided with a grouting hole (121) that communicates with the grouting groove.

Images