Adjustable diagonal bracing method

Abstract

The application provides a kind of adjustable inclined support method, adopts enclosure pile, pressure top beam, slide rail, horizontal support, advanced inclined support and movable inclined support, at least one parallel movable inclined support is arranged below advanced inclined support, horizontal support and movable inclined support are all length telescopic prefabricated support, one end of horizontal support is slidably connected with slide rail, the other end is slidably connected with advanced inclined support, upper end of movable inclined support is slidably connected with slide rail, lower end is slidably connected with horizontal support and the angle between movable inclined support and horizontal support can be adjusted, horizontal support can be realized with excavation surface moving down, the support position of movable inclined support is flexibly adjustable, stable triangle structure is formed by enclosure pile, advanced inclined support and horizontal support, and the overall stability and adaptability of support system are improved by adding movable inclined support, combined with three-dimensional connection reinforcement measures, construction process is simplified, construction period is shortened, construction cost and safety risk are reduced.

Description

Technical Field

[0001] This invention relates to the field of foundation pit support engineering technology, specifically to an adjustable inclined bracing support method, which is applicable to the excavation support of various types of building foundation pits, especially to deep foundation pits in soft soil areas, large-area excavated foundation pits, and foundation pit projects with complex surrounding environments. It can effectively improve support stability and increase construction efficiency. Background Technology

[0002] For foundation pits with shallow excavation depths, when the pit area is large or the distance between the pit edge and the land boundary line is insufficient, a bracing system is generally used. Conventional bracing systems have drawbacks such as complex construction procedures, cumbersome processes, difficulty in excavating soil around the pit edge, the need for secondary pouring of the foundation slab, and the risk of water leakage after cutting the main building's foundation slab. A self-stabilizing foundation pit support system using advanced bracing piles instead of inclined supports can solve problems such as soil retention around the pit edge and secondary pouring of the foundation slab. However, the support points of the bracing are mostly fixed in design, making it impossible to adjust the support point positions according to changes in soil stress and excavation depth during the excavation process. This makes it difficult to adapt to the support needs of different excavation stages. When the excavation depth is large or the soil properties are uneven, uneven support stress and localized stress concentration can easily occur, leading to safety hazards such as foundation pit slope collapse and retaining structure deformation.

[0003] Therefore, developing a new type of inclined bracing support system that can achieve synchronous movement of horizontal supports with the excavation face, adjustable position of inclined bracing support points, form a three-dimensional stable support structure, and is convenient, safe and reliable to construct has become an urgent technical problem to be solved in the field of foundation pit support engineering. Summary of the Invention

[0004] To overcome the shortcomings of existing inclined bracing support methods, such as the inability to adjust the support position, insufficient support stability, large deformation of the foundation pit retaining wall, and poor adaptability, this invention provides an adjustable inclined bracing support method. This method enables the horizontal support to move at intervals with the excavation face and allows for flexible adjustment of the inclined bracing support point position. A stable triangular structure is formed by retaining piles, advanced inclined bracing, and horizontal support. Furthermore, by adding movable inclined bracing, the overall stability and adaptability of the support system are improved, simplifying construction procedures, shortening the construction period, and reducing construction costs and safety risks.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] This invention discloses an adjustable diagonal bracing support method, comprising the following steps:

[0007] Step 1: Construct retaining piles, advanced inclined braces, and sliding rails. The advanced inclined braces are obliquely installed inside the retaining piles. The sliding rails are installed along the inner wall of the retaining piles. Construct the retaining piles and advanced inclined braces along the edge of the foundation pit. The lower end of the advanced inclined brace extends into the soil at the bottom of the foundation pit, and the upper end of the advanced inclined brace is close to the corresponding retaining pile. The vertical plane containing the axis of the advanced inclined brace is perpendicular to the edge of the foundation pit, and the axis of the corresponding retaining pile is located in the vertical plane containing the axis of the advanced inclined brace. The sliding rails are installed along the height direction on the inner wall of the retaining pile corresponding to the advanced inclined brace.

[0008] Step 2: Excavate to the bottom of the capping beam, construct the capping beam on top of the retaining piles, and fix the upper end of the advanced diagonal brace to the capping beam.

[0009] Step 3: Excavate to the depth required for installing horizontal supports;

[0010] Step 4: Place the horizontal support horizontally on the excavation surface. The horizontal support is a prefabricated support component with an extendable length. One end of the horizontal support is slidably connected to and locked on the slide rail, and the other end of the horizontal support is slidably connected to the advanced inclined brace.

[0011] Step 5: Excavate to the depth of the foundation pit where a movable diagonal brace needs to be installed;

[0012] Step 6: Slide the horizontal support down onto the excavation surface and lock it in place;

[0013] Step 7: Add a movable diagonal brace. The lower end of the movable diagonal brace is slidably connected to the horizontal support, and the upper end of the movable diagonal brace is slidably connected to the slide rail. The movable diagonal brace is a support member whose length can be extended or retracted. The lower end of the movable diagonal brace is evenly placed on the horizontal support and locked on the horizontal support. The angle between the movable diagonal brace and the horizontal support can be adjusted. Adjust the position of the upper end of the movable diagonal brace on the slide rail so that the movable diagonal brace is parallel to the leading diagonal brace. Lock the upper end of the movable diagonal brace on the slide rail.

[0014] Step 8: Continue excavation. If the excavation reaches the depth where the next movable brace needs to be installed, release the locking between the slide rail, horizontal support, and movable brace. Slide the horizontal support down to the excavation surface and then lock it again. Repeat step 7 until the excavation reaches a depth of 1.5m to 2m above the pit bottom or directly to the pit bottom. If the excavation reaches a depth of 1.5m to 2m above the pit bottom, proceed to step 9; if the excavation directly to the pit bottom, proceed to step 11.

[0015] Step 9: Slide the horizontal support down to the excavation face and lock it. Add a movable diagonal brace. Place the lower end of the movable diagonal brace evenly on the horizontal support and lock it. Adjust each movable diagonal brace to be parallel with the advanced diagonal brace, and then lock the upper end of each movable diagonal brace on the slide rail.

[0016] Step 10: Continue excavating to the bottom of the pit;

[0017] Step 11: Construct the foundation slab.

[0018] Preferably, in the above-described adjustable diagonal bracing support method, after step 11, the method further includes:

[0019] Step 12: Remove one or two movable diagonal braces, slide the horizontal support up one basement floor height and lock it, adjust the position of the lower end of the movable diagonal brace so that the movable diagonal brace is evenly distributed on the horizontal support, adjust the position of the upper end of the movable diagonal brace so that the movable diagonal brace is parallel to the advanced diagonal brace; construct the basement exterior wall, vertical structure and adjacent floor slabs of the corresponding floor, and backfill the gap between the basement exterior wall and the retaining piles.

[0020] Step 13: Repeat step 12, continue construction of the basement exterior walls and vertical structure of the corresponding floor and the floor slabs of the adjacent floor from bottom to top, and backfill the gap between the basement exterior walls and the retaining piles until the distance between the horizontal support and the ground is less than 3m.

[0021] Step 14: Remove the horizontal supports and movable diagonal braces, and continue construction of the basement structure until the top slab is completed;

[0022] Step 15: After the backfill between the basement exterior wall and the retaining piles is compacted, cut off the section of the advanced diagonal brace located above the foundation slab, and seal and repair the holes in the foundation slab, each floor slab, and the roof slab through which the advanced diagonal brace passes.

[0023] Preferably, in the above-mentioned adjustable diagonal bracing support method, two adjacent horizontal supports are connected by two connecting rods, and two scissor braces are arranged in a cross pattern between the two connecting rods; the two scissor braces are hinged to each other in the middle, and the length of the scissor braces themselves can be extended or retracted; the distance between the two connecting rods changes synchronously with the extension and retraction of the horizontal supports: when the horizontal supports extend, the distance between the connecting rods increases synchronously, and the scissor braces lengthen synchronously; when the horizontal supports shorten, the distance between the connecting rods decreases synchronously, and the scissor braces shorten synchronously.

[0024] Preferably, in the above-mentioned adjustable diagonal bracing support method, in step 4, connecting rods are installed near the retaining piles; in step 6, connecting rods and scissor braces are installed near the advanced diagonal braces; and in step 14, all connecting rods and scissor braces are removed.

[0025] Preferably, in the above-described adjustable diagonal brace support method, the end of the horizontal support near the advanced diagonal brace is slidably connected to the advanced diagonal brace via a first sliding sleeve. The first sliding sleeve is fitted onto the advanced diagonal brace and can slide along the axis of the advanced diagonal brace. The end of the horizontal support near the advanced diagonal brace is hinged to the first sliding sleeve.

[0026] Preferably, in the above-mentioned adjustable diagonal brace support method, in step 4, the first sliding sleeve is fitted on the outside of the advanced diagonal brace, the first sliding sleeve can slide relative to the advanced diagonal brace, and the other end of the horizontal support is hinged to the first sliding sleeve.

[0027] Preferably, in the above-described adjustable diagonal brace support method, the horizontal support includes a fixed section and a movable section. The end of the fixed section away from the advanced diagonal brace is slidably connected to a slide rail. One end of the movable section extends into the inner side of the fixed section near the advanced diagonal brace. The other end of the movable section is slidably connected to the advanced diagonal brace.

[0028] Preferably, in the above-described adjustable diagonal brace support method, the fixed section is an outer sleeve, the movable section is a single inner rod, one end of the outer sleeve is slidably connected to the slide rail, one end of the inner rod extends into the inner side of the other end of the outer sleeve, and the other end of the inner rod is slidably connected to the advanced diagonal brace.

[0029] Preferably, in the above-mentioned adjustable diagonal brace support method, the fixed section is an outer sleeve, and the movable section is a plurality of telescopic inner rods that are sequentially nested inside the outer sleeve. The end of the outer sleeve away from the advanced diagonal brace is slidably connected to the slide rail, and the end of the innermost inner rod away from the slide rail is slidably connected to the advanced diagonal brace.

[0030] Preferably, in the above-described adjustable diagonal brace support method, the lower end of the movable diagonal brace is connected to the horizontal support via a second sliding sleeve and a bolt assembly. The second sliding sleeve is fitted onto the rod of the horizontal support. The lower end of the movable diagonal brace is hinged to the upper part of the second sliding sleeve. The horizontal support has multiple sets of through holes spaced at equal intervals along the axial direction of the rod. A set of through holes is provided in the middle of the second sliding sleeve. When the bolt assembly is loosened, the second sliding sleeve can slide along the horizontal support. By tightening the bolt assembly, the second sliding sleeve can be fixed at any specified position on the horizontal support.

[0031] Preferably, in the above-described adjustable diagonal brace support method, the ends of the horizontal support near the slide rail and the ends of the movable diagonal brace near the slide rail are respectively provided with sliders that match the slide rail. The ends of the horizontal support near the slide rail and the ends of the movable diagonal brace near the slide rail are respectively provided with locking elements. These locking elements can lock the ends of the horizontal support and the upper ends of the movable diagonal brace onto the slide rail. After the locking elements are released, the sliders can slide freely up and down along the slide rail. Because the locking elements can fix the ends of the horizontal support onto the slide rail, when the horizontal support moves to the designated excavation face position, the corresponding locking elements fix the horizontal support to the slide rail, preventing displacement of the horizontal support and ensuring the support stability of the horizontal support.

[0032] As can be seen from the above-disclosed technical solutions, compared with the prior art, the beneficial effects of the adjustable diagonal bracing support method provided by the present invention are as follows:

[0033] On the one hand, the present invention uses an advanced inclined brace as the first inclined brace, that is, the first inclined support. The first inclined brace adopts the form of an inclined advanced inclined brace, and its support point is fixed. One end is fixedly connected to the capping beam at the top of the retaining pile, and the other end extends into the soil at the bottom of the foundation pit. It can play a supporting role in advance before excavation and effectively control the soil deformation in the early stage of foundation pit excavation.

[0034] On the other hand, the movable bracing can be installed gradually according to the excavation progress. The upper end of the movable bracing is slidably connected to the slide rail and can be locked on the slide rail. Therefore, the movable bracing can move down with the horizontal support, so that the support position of the movable bracing changes with the position of the horizontal support, adapting to the support stress requirements of different excavation stages. The lower end of the movable bracing is slidably connected to the horizontal support and can be locked on the horizontal support. By adjusting the position of the movable bracing on the horizontal support, the movable bracing can be evenly distributed on the horizontal support. By adjusting the position of the movable bracing on the slide rail, the support position of the upper end of the movable bracing on the slide rail can be adjusted, so that the movable bracing and the advanced bracing are parallel to each other, thereby evenly transferring the load of the retaining pile to the foundation and ensuring the stability of the support stress at different excavation stages.

[0035] On the other hand, during the construction of the basement structure, the horizontal support can slide upward and lock as the basement structure is gradually rebuilt. The movable diagonal brace can be gradually disassembled and assembled according to the excavation progress. The movable diagonal brace can move upward with the horizontal support, so that the support position of the movable diagonal brace changes with the position of the horizontal support, adapting to the support stress requirements of different rebuilt stages of the basement.

[0036] Furthermore, the retaining piles, inclined supports (including advanced inclined supports and movable inclined supports), and horizontal supports are interconnected to form a stable triangular structure. Utilizing the stability principle of triangles, the lateral pressure of the soil around the foundation pit is smoothly transferred to the foundation, playing an overall supporting role, improving the overall support strength, and effectively resisting the lateral displacement and overturning of the soil. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of step 1 of an embodiment of the adjustable diagonal bracing support method of the present invention.

[0038] Figure 2 This is a schematic diagram of step 2 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0039] Figure 3 This is a schematic diagram of step 3 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0040] Figure 4This is a structural schematic diagram of step 4 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0041] Figure 5 This is a structural schematic diagram of step 5 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0042] Figure 6 This is a schematic diagram of step 6 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0043] Figure 7 This is a structural schematic diagram of step 7 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0044] Figure 8 This is a structural schematic diagram of step 8 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0045] Figure 9 This is a structural schematic diagram of step 9 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0046] Figure 10 This is a structural schematic diagram of step 10 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0047] Figure 11 This is a structural schematic diagram of step 11 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0048] Figure 12 This is a schematic diagram of step 1 of an embodiment of the adjustable diagonal bracing support method of the present invention.

[0049] Figure 13 This is a structural schematic diagram of step 13 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0050] Figure 14 This is a structural schematic diagram of step 14 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0051] Figure 15 This is a structural schematic diagram of step 15 in an embodiment of the adjustable diagonal bracing support method of the present invention.

[0052] Figure 16 This is a schematic diagram of the assembly of the connecting rod, scissor brace, and horizontal support in an embodiment of an adjustable diagonal bracing support method of the present invention.

[0053] Figure 17 This is a structural schematic diagram of step 7 in an embodiment 2 of the adjustable diagonal bracing support method of the present invention.

[0054] Figure 18This is a structural schematic diagram of step 15 in Embodiment 2 of the adjustable diagonal bracing support method of the present invention.

[0055] In the diagram: 1-Retaining pile, 2-Sliding rail, 3-Advanced diagonal brace, 4-Top beam, 5-Horizontal support, 6-Modible diagonal brace, 7-First sliding sleeve, 8-Second sliding sleeve, 9-Connecting rod, 10-Scissor brace, 11-Foundation slab, 12-Basement exterior wall, 13-Floor slab, 14-Top slab, 15-Backfill compaction section, 16-Ground surface, 17-Excavation face, 18-Pit bottom. Detailed Implementation

[0056] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The technical content and features of the present invention will be described in detail below with reference to the listed embodiments and the accompanying drawings. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention. For ease of description, the terms "upper" and "lower" used below are consistent with the upper and lower directions in the accompanying drawings, but this should not be construed as a limitation of the technical solution of the present invention.

[0057] Example 1

[0058] Please see Figures 1 to 16 In this embodiment, the excavation depth of the foundation pit is 12m, and the basement structure has two floors. An adjustable inclined bracing support method according to this embodiment includes the following steps:

[0059] Step 1: Construct retaining piles 1, advanced inclined braces 3, and sliding rails 2. The advanced inclined braces 3 are obliquely installed on the inner side of the retaining piles 1. The sliding rails 2 are installed along the inner wall of the retaining piles 1. Specifically, the retaining piles 1 are constructed along the edge of the foundation pit, and the advanced inclined braces 3 are constructed. The lower end of the advanced inclined braces 3 extends into the soil at the bottom of the foundation pit, and the upper end of the advanced inclined braces 3 is close to the corresponding retaining pile 1. The vertical plane containing the axis of the advanced inclined braces 3 is perpendicular to the edge of the foundation pit, and the axis of the corresponding retaining pile 1 is located in the vertical plane containing the axis of the advanced inclined braces 3. The sliding rails 2 are installed along the height direction on the inner wall of the retaining pile 1 corresponding to the advanced inclined braces 3.

[0060] Step 2: Excavate to the bottom of the capping beam 4, construct the capping beam 4 on top of the retaining pile 1, and fix the upper end of the advanced diagonal brace 3 to the capping beam 4.

[0061] Step 3: Excavate to the depth where horizontal supports 5 need to be installed; usually, horizontal supports 5 need to be installed when excavating to 3m below 16m from the ground.

[0062] Step 4: Place the horizontal support 5 horizontally on the excavation face 17. The horizontal support 5 is a prefabricated support component with an extendable length. One end of the horizontal support 5 is slidably connected to the slide rail 2 and locked on the slide rail 2, and the other end of the horizontal support 5 is slidably connected to the advanced inclined brace 3.

[0063] Step 5: Excavate to the depth required to install one movable diagonal brace 6; in this embodiment, excavate 2.5m~3m to reach the depth required to install one movable diagonal brace 6.

[0064] Step 6: Slide the horizontal support 5 down onto the excavation face 17 and lock it. Before sliding the horizontal support 5 down, first release the lock between the slide rail 2 and the horizontal support 5.

[0065] Step 7: Add a movable diagonal brace 6. The lower end of the movable diagonal brace 6 is slidably connected to the horizontal support 5, and the upper end of the movable diagonal brace 6 is slidably connected to the slide rail 2. The movable diagonal brace 6 is a support member whose length can be extended or retracted. The lower end of the movable diagonal brace 6 is evenly placed on the horizontal support 5 and locked on the horizontal support 5. The angle between the movable diagonal brace 6 and the horizontal support 5 can be adjusted. Adjust the position of the upper end of the movable diagonal brace 6 on the slide rail 2 so that the movable diagonal brace 6 is parallel to the advanced diagonal brace 3. Lock the upper end of the movable diagonal brace 6 on the slide rail 2.

[0066] Step 8: Continue excavation. If the excavation reaches the depth where the next movable diagonal brace 6 needs to be added, release the lock between the slide rail 2, the horizontal support 5, and the movable diagonal brace 6. Slide the horizontal support 5 down to the excavation surface 17 and then lock it again. Repeat step 7 until the excavation reaches a range of 1.5m to 2m above the pit bottom 18 or directly reaches the pit bottom 18. If the excavation reaches a range of 1.5m to 2m above the pit bottom, proceed to step 9; if the excavation directly reaches the pit bottom 18, proceed to step 11.

[0067] Step 9: Slide the horizontal support 5 down to the excavation face 17 and lock it. Add a movable diagonal brace 6. Place the lower end of the movable diagonal brace 6 evenly on the horizontal support 5 and lock it. Adjust each movable diagonal brace 6 to be parallel to the advanced diagonal brace 3, and then lock the upper end of each movable diagonal brace 6 on the slide rail 2.

[0068] Step 10: Continue excavating to the bottom of the pit, 18.

[0069] Step 11, construct the foundation slab 11.

[0070] As can be seen from the above, the adjustable inclined bracing method provided by the present invention, on the one hand, adopts the advanced inclined bracing 3 as the first inclined bracing, that is, the first inclined support. The inclined support includes movable support and advanced support. The first inclined bracing adopts the form of inclined advanced inclined bracing 3, whose support point position is fixed. One end is fixedly connected to the top pressure beam 4 of the retaining pile 1, and the other end extends into the soil at the bottom of the foundation pit. It can play a supporting role in advance before excavation and effectively control the soil deformation in the early stage of foundation pit excavation.

[0071] On the other hand, the movable diagonal brace 6 can be installed gradually according to the excavation progress. The upper end of the movable diagonal brace 6 is slidably connected to the slide rail 2 and can be locked on the slide rail 2. Therefore, the movable diagonal brace 6 can move down with the horizontal support 5, so that the support position of the movable diagonal brace 6 changes with the position of the horizontal support 5, adapting to the support force requirements of different excavation stages. The lower end of the movable diagonal brace 6 is slidably connected to the horizontal support 5 and can be locked on the horizontal support 5. By adjusting the position of the movable diagonal brace 6 on the horizontal support 5, the movable diagonal brace 6 can be evenly distributed on the horizontal support 5. By adjusting the position of the movable diagonal brace 6 on the slide rail 2, the support position of the upper end of the movable diagonal brace 6 on the slide rail 2 can be adjusted, so that the movable diagonal brace 6 and the advanced diagonal brace 3 are parallel to each other, thereby evenly transferring the load of the retaining pile 1 to the foundation and ensuring the stability of the support force at different excavation stages.

[0072] On the other hand, the retaining piles 1, the inclined supports (including the advanced inclined supports 3 and the movable inclined supports 6) and the horizontal supports 5 are interconnected to form a stable triangular structure. By utilizing the stability principle of triangles, the lateral pressure of the soil around the foundation pit is smoothly transferred to the foundation, playing an overall supporting role, improving the overall support strength, and effectively resisting the lateral displacement and overturning of the soil.

[0073] Preferably, in the above-described adjustable diagonal bracing support method, after step 11, the method further includes:

[0074] Step 12: Remove one or two movable diagonal braces 6, slide the horizontal support 5 up one basement floor height and lock it to facilitate the construction of the adjacent floor slab to be constructed, adjust the position of the lower end of the movable diagonal brace 6 so that the movable diagonal brace 6 is evenly distributed on the horizontal support 5, adjust the position of the upper end of the movable diagonal brace 6 so that the movable diagonal brace 6 is parallel to the advanced diagonal brace 3; construct the basement exterior wall 12, vertical structure and adjacent floor slab 13 of the corresponding floor, and backfill the gap between the basement exterior wall 12 and the retaining pile 1.

[0075] Step 13: Repeat step 12, continuing construction from bottom to top on the corresponding basement exterior wall 12, vertical structure, and adjacent floor slabs 13, and backfilling the gap between the basement exterior wall 12 and the retaining piles 1, until the distance between the horizontal support 5 and the ground 16 is less than 3m. In this embodiment, by backfilling the gap between the basement exterior wall 12 and the retaining piles 1, a compacted backfill section 15 is formed, enabling the foundation slab, basement exterior wall, and other constructed underground structures to effectively support the retaining piles, further improving the stability of the foundation pit.

[0076] Step 14: Remove horizontal support 5 and the remaining movable diagonal brace 6, and continue construction of the basement structure until the top slab 14 is completed.

[0077] Step 15: After the backfill between the basement exterior wall 12 and the retaining pile 1 is compacted, cut off the section of the advanced diagonal brace 3 above the foundation slab 11, and seal and repair the holes in the foundation slab 11, each floor slab and the top slab 14 through which the advanced diagonal brace 3 passes.

[0078] As can be seen from the above, when the basement structure is being constructed, the horizontal support can slide upward and lock as the basement structure is gradually rebuilt. The movable diagonal brace can be installed gradually according to the excavation progress. The movable diagonal brace can move upward with the horizontal support, so that the support position of the movable diagonal brace changes with the position of the horizontal support, adapting to the support force requirements of different basement rebuilt stages.

[0079] Preferably, in the above-described adjustable diagonal bracing method, adjacent horizontal supports 5 are connected by two connecting rods 9. Two scissor braces 10 are arranged in a cross configuration between the two connecting rods 9. The two scissor braces 10 are hinged together at the middle. The length of each scissor brace 10 is extendable and retractable. The distance between the two connecting rods 9 changes synchronously with the extension and retraction of the horizontal support 5: when the horizontal support 5 extends, the distance between the connecting rods 9 increases synchronously, and the scissor braces 10 lengthen synchronously; when the horizontal support 5 shortens, the distance between the connecting rods 9 decreases synchronously, and the scissor braces 10 shorten synchronously. In other words, the distance between the two connecting rods 9 changes synchronously with the length of the horizontal support 5. When the horizontal support 5 extends, the distance between the two connecting rods 9 increases accordingly, and the length of the scissor braces 10 lengthens accordingly. When the horizontal support 5 shortens, the distance between the two connecting rods 9 shortens accordingly, and the length of the scissor braces 10 shortens accordingly. A connecting rod 9 and a scissor brace 10 are added between adjacent movable diagonal braces 6 and horizontal supports 5. Both the connecting rod 9 and the scissor brace 10 are prefabricated steel components, which can be detachably connected to the movable diagonal braces 6 and horizontal supports 5 to form a three-dimensional support system, further improving the overall rigidity and stability of the support system and effectively avoiding local support instability and damage.

[0080] Preferably, in the above-mentioned adjustable diagonal bracing support method, in step 4, the connecting rod 9 close to the retaining pile 1 is installed; in step 6, the connecting rod 9 close to the advanced diagonal brace 3 and the scissor brace 10 are installed; in step 14, all connecting rods 9 and scissor braces 10 are removed.

[0081] Preferably, in the above-described adjustable diagonal brace support method, the end of the horizontal support 5 near the advanced diagonal brace 3 is slidably connected to the advanced diagonal brace 3 via a first sliding sleeve 7. The first sliding sleeve 7 is sleeved on the rod of the advanced diagonal brace 3 and can slide along the axis of the advanced diagonal brace 3. The end of the horizontal support 5 near the advanced diagonal brace 3 is hinged to the first sliding sleeve 7.

[0082] Preferably, in the above-mentioned adjustable diagonal brace support method, in step 4, the first sliding sleeve 7 is fitted on the outside of the advanced diagonal brace 3, the first sliding sleeve 7 can slide relative to the advanced diagonal brace 3, and the other end of the horizontal support 5 is hinged to the first sliding sleeve 7.

[0083] Preferably, in the above-described adjustable diagonal brace support method, the lower end of the movable diagonal brace 6 is connected to the horizontal support 5 via a second sliding sleeve 8 and a bolt assembly. The second sliding sleeve 8 is fitted onto the horizontal support 5, thereby achieving a sliding connection between the lower end of the movable diagonal brace 6 and the horizontal support 5, allowing the lower end of the movable diagonal brace 6 to move along the horizontal support 5. The lower end of the movable diagonal brace 6 is hinged to the upper part of the second sliding sleeve 8, thereby enabling angle adjustment between the movable diagonal brace 6 and the horizontal support 5. The horizontal support 5 has several pairs of through holes evenly spaced along its own axial direction, and the second sliding sleeve 8 has a pair of through holes in its middle. The bolt assembly can lock the second sliding sleeve 8 in the desired position on the horizontal support 5; when the bolt assembly is loosened, the second sliding sleeve 8 can slide relative to the horizontal support 5.

[0084] Preferably, in the above-described adjustable diagonal brace support method, the horizontal support 5 includes a fixed section and a movable section. The end of the fixed section away from the advanced diagonal brace 3 is slidably connected to the slide rail 2. One end of the movable section extends into the inner side of the fixed section near the advanced diagonal brace 3, and the other end of the movable section is slidably connected to the advanced diagonal brace 3.

[0085] Preferably, in the above-mentioned adjustable diagonal brace support method, the fixed section is an outer sleeve, and the movable section is a plurality of telescopic inner rods that are sequentially nested inside the outer sleeve. The end of the outer sleeve away from the advanced diagonal brace 3 is slidably connected to the slide rail 2, and the end of the innermost inner rod away from the slide rail 2 is slidably connected to the advanced diagonal brace 3.

[0086] Preferably, in the above-described adjustable diagonal brace support method, the lower end of the movable diagonal brace 6 is connected to the horizontal support 5 via a second sliding sleeve 8 and a bolt assembly. The second sliding sleeve 8 is sleeved on the rod of the horizontal support 5. The lower end of the movable diagonal brace 6 is hinged to the upper part of the second sliding sleeve 8. The horizontal support 5 has multiple sets of through holes at equal intervals along the axial direction of the rod. The second sliding sleeve 8 has a set of through holes in the middle. When the bolt assembly is loosened, the second sliding sleeve 8 can slide relative to the horizontal support 5. The locking bolt assembly can fix the second sliding sleeve 8 at any specified position of the horizontal support 5. Since the second sliding sleeve 8 is fitted onto the horizontal support 5, the lower end of the movable diagonal brace 6 can slide along the horizontal support 5, thereby adjusting the position of the lower end of the movable diagonal brace 6 on the horizontal support 5. Since the lower end of the movable diagonal brace 6 is hinged to the upper part of the second sliding sleeve 8, the angle between the movable diagonal brace 6 and the horizontal support 5 can be adjusted. Furthermore, since the upper end of the movable diagonal brace 6 is slidably connected to the slide rail 2, the movable diagonal brace 6 can be parallel to the advanced diagonal brace 3, thereby adapting to the support force requirements of different excavation stages and evenly transferring the load of the retaining pile 1 to the foundation.

[0087] Preferably, in the above-described adjustable diagonal brace support method, the ends of the horizontal support 5 near the slide rail 2 and the ends of the movable diagonal brace 6 near the slide rail 2 are respectively provided with sliders matching the slide rail 2. The ends of the horizontal support 5 near the slide rail 2 and the ends of the movable diagonal brace 6 near the slide rail 2 are respectively provided with locking components. These locking components can lock the ends of the horizontal support 5 and the upper ends of the movable diagonal brace 6 onto the slide rail 2. After releasing the locking components, the sliders can slide freely up and down along the slide rail 2. The locking components can be bolt assemblies or clamp structures. Because the locking components can fix the ends of the horizontal support 5 onto the slide rail 2, when the horizontal support 5 moves to the designated excavation face position, the corresponding locking components fix the horizontal support 5 to the slide rail 2, preventing displacement of the horizontal support 5 and ensuring the support stability of the horizontal support 5. Before the horizontal support 5 moves up and down, the lock between the slide rail 2 and the horizontal support 5 needs to be released.

[0088] Preferably, both the first sliding sleeve 7 and the second sliding sleeve 8 are hoop-type components, which facilitate installation and sliding.

[0089] Preferably, the horizontal support 5, movable diagonal brace 6, connecting rod 9 and scissor brace 10 are all prefabricated from high-strength steel. The prefabricated components are standardized in size and modularly customized, and can be directly installed on site without on-site pouring, which greatly shortens the construction period. In addition, the prefabricated components can be reused, reducing construction costs.

[0090] Example 2

[0091] Please see Figure 17 and Figure 18 And can be consulted in conjunction with other references. Figures 1 to 16 The difference between this embodiment and Embodiment 1 is that the excavation depth of the foundation pit is 7m, the basement structure has only one floor, and only one movable diagonal brace 6 is needed. The fixed section of the horizontal support 5 is an outer sleeve, and the movable section is a single inner rod. One end of the outer sleeve is slidably connected to the slide rail 2, one end of the inner rod extends into the inner side of the other end of the outer sleeve, and the other end of the inner rod is slidably connected to the advanced diagonal brace 3.

[0092] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. An adjustable diagonal bracing support method, characterized in that, include: Step 1: Construct retaining piles, advanced inclined braces, and sliding rails. The advanced inclined braces are obliquely installed on the inner side of the retaining piles, and the sliding rails are installed along the entire length of the inner wall of the retaining piles. Step 2: Excavate to the bottom of the capping beam, construct the capping beam on top of the retaining piles, and fix the upper end of the advanced diagonal brace to the capping beam. Step 3: Excavate to the depth required for installing horizontal supports; Step 4: Place the horizontal support horizontally on the excavation surface. The horizontal support is a prefabricated support component with an extendable length. One end of the horizontal support is slidably connected to the slide rail and locked on the slide rail, and the other end of the horizontal support is slidably connected to the advanced inclined brace. Step 5: Excavate to the depth of the foundation pit where a movable diagonal brace needs to be installed; Step 6: Slide the horizontal support down onto the excavation surface and lock it in place; Step 7: Add a movable diagonal brace. The lower end of the movable diagonal brace is slidably connected to the horizontal support, and the upper end of the movable diagonal brace is slidably connected to the slide rail. The movable diagonal brace is a support component whose length can be extended or retracted. The lower end of the movable diagonal brace is evenly placed on the horizontal support and locked. The angle between the movable diagonal brace and the horizontal support can be adjusted. Adjust the position of the upper end of the movable diagonal brace on the slide rail so that the movable diagonal brace is parallel to the leading diagonal brace, and lock the upper end of the movable diagonal brace on the slide rail. Step 8: Continue excavation. If the excavation reaches the depth where the next movable brace needs to be installed, release the locking between the slide rail, horizontal support, and movable brace. Slide the horizontal support down to the excavation surface and then lock it again. Repeat step 7 until the excavation reaches a depth of 1.5m to 2m above the pit bottom or directly to the pit bottom. If the excavation reaches a depth of 1.5m to 2m above the pit bottom, proceed to step 9; if the excavation directly to the pit bottom, proceed to step 11. Step 9: Slide the horizontal support down to the excavation face and lock it. Add a movable diagonal brace. Place the lower end of the movable diagonal brace evenly on the horizontal support and lock it. Adjust each movable diagonal brace to be parallel with the advanced diagonal brace, and then lock the upper end of each movable diagonal brace on the slide rail. Step 10: Continue excavating to the bottom of the pit; Step 11: Construct the foundation slab.

2. The adjustable diagonal bracing support method as described in claim 1, characterized in that, After step 11, it also includes: Step 12: Remove one or two movable diagonal braces, slide the horizontal support up one basement floor height and lock it, adjust the position of the lower end of the movable diagonal brace so that the movable diagonal brace is evenly distributed on the horizontal support, adjust the position of the upper end of the movable diagonal brace so that the movable diagonal brace is parallel to the advanced diagonal brace; construct the basement exterior wall, vertical structure and adjacent floor slabs of the corresponding floor, and backfill the gap between the basement exterior wall and the retaining piles. Step 13: Repeat step 12, continue construction of the basement exterior walls and vertical structure of the corresponding floor and the floor slabs of the adjacent floor from bottom to top, and backfill the gap between the basement exterior walls and the retaining piles until the distance between the horizontal support and the ground is less than 3m. Step 14: Remove the horizontal supports and movable diagonal braces, and continue construction of the basement structure until the top slab is completed; Step 15: After the backfill between the basement exterior wall and the retaining piles is compacted, cut off the section of the advanced diagonal brace located above the foundation slab, and seal and repair the holes in the foundation slab, each floor slab, and the roof slab through which the advanced diagonal brace passes.

3. The adjustable diagonal bracing support method as described in claim 1, characterized in that, Two adjacent horizontal supports are connected by two connecting rods, and two scissor braces are arranged in a cross pattern between the two connecting rods; the two scissor braces are hinged to each other in the middle, and the length of the scissor braces can be extended or retracted; the distance between the two connecting rods changes synchronously with the extension and retraction of the horizontal supports: when the horizontal supports extend, the distance between the connecting rods increases synchronously, and the scissor braces lengthen synchronously; when the horizontal supports shorten, the distance between the connecting rods decreases synchronously, and the scissor braces shorten synchronously.

4. The adjustable diagonal bracing support method as described in claim 2, characterized in that, In step 4, install the connecting rods close to the retaining piles; in step 6, install the connecting rods close to the forward diagonal bracing and the scissor bracing; in step 14, remove all the connecting rods and scissor bracing.

5. The adjustable diagonal bracing support method as described in claim 1, characterized in that, The end of the horizontal support near the advanced diagonal brace is slidably connected to the advanced diagonal brace via a first sliding sleeve; the first sliding sleeve is fitted onto the advanced diagonal brace rod and can slide along the axis of the advanced diagonal brace, and the end of the horizontal support near the advanced diagonal brace is hinged to the first sliding sleeve.

6. The adjustable diagonal bracing support method as described in claim 1, characterized in that, The horizontal support includes a fixed section and a movable section. The end of the fixed section away from the leading diagonal brace is slidably connected to the slide rail. One end of the movable section extends into the inner side of the fixed section near the leading diagonal brace. The other end of the movable section is slidably connected to the leading diagonal brace.

7. The adjustable diagonal bracing support method as described in claim 6, characterized in that, The fixed section is an outer sleeve, and the movable section is a single inner rod. One end of the outer sleeve is slidably connected to the slide rail, and one end of the inner rod extends into the inner side of the other end of the outer sleeve. The other end of the inner rod is slidably connected to the advanced diagonal brace.

8. The adjustable diagonal bracing support method as described in claim 6, characterized in that, The fixed section is an outer sleeve, and the movable section consists of multiple telescopic inner rods that are sequentially nested inside the outer sleeve. The end of the outer sleeve away from the leading diagonal brace is slidably connected to the slide rail, and the end of the innermost inner rod away from the slide rail is slidably connected to the leading diagonal brace.

9. The adjustable diagonal bracing support method as described in claim 1, characterized in that, The lower end of the movable diagonal brace is connected to the horizontal support via a second sliding sleeve and a bolt assembly. The second sliding sleeve is fitted onto the horizontal support rod. The lower end of the movable diagonal brace is hinged to the upper part of the second sliding sleeve. The horizontal support has multiple sets of through holes at equal intervals along the axial direction of the rod. The second sliding sleeve has a set of through holes in the middle. When the bolt assembly is loosened, the second sliding sleeve can slide along the horizontal support. When the bolt assembly is tightened, the second sliding sleeve can be fixed at any specified position on the horizontal support.

10. The adjustable diagonal bracing support method as described in claim 1, characterized in that, The horizontal support and the movable diagonal brace are respectively provided with sliders that match the slide rail at their ends near the slide rail. The horizontal support and the movable diagonal brace are respectively provided with locking members. The ends of the horizontal support and the upper ends of the movable diagonal brace can be locked onto the slide rail by the corresponding locking members. After the locking members are released, the sliders can slide freely up and down along the slide rail.

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