Efficient support changing system for deep and large foundation pit

Abstract

The utility model relates to a deep and large foundation pit efficient support changing system which comprises a foundation pit waterproof curtain, a safety protection channel, a steel pipe inner support and a profile steel inner support, a grouting hole is formed in the ground of the upper portion of a water leakage point of the foundation pit waterproof curtain, and a water diversion pipe is arranged in the water leakage point in the horizontal direction. And a hanging construction platform is mounted between the latticed columns in the foundation pit. The foundation pit secant pile water seepage device has the advantages that on the basis of cement stone blocking and secondary grouting, water in foundation soil is drained into the water diversion pipe through the horizontally-arranged water diversion pipe, water pressure balance in the pipe is achieved through the vertically-lengthened water diversion pipe by means of atmospheric pressure, dynamic adjustment is achieved through the arrangement of the water pumping device in an auxiliary mode, and the water seepage problem of a foundation pit secant pile is solved. The foundation pit secant pile leakage blocking effect is greatly improved; a traditional concrete beam support is replaced by a hoop type profile steel inner support, the problem that the slenderness ratio and the stress ratio of a steel pipe column exceed the limit in the deep foundation pit excavation process is effectively solved, and meanwhile the safety of foundation pit supporting and an upper structure is guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of foundation and substructure engineering technology, and in particular to an efficient replacement support system for deep and large foundation pits. Background Art

[0002] With the continuous development of cities and the improvement of construction technology, the utilization of underground space is becoming more and more common. The excavation depth of foundation pits is increasing, and the distance between the sidewalls of the foundation pits and the surrounding buildings (structures) is getting smaller and smaller. The difficulty of foundation pit construction is increasing, and the problems that need to be solved are also increasing.

[0003] For example, interlocking piles for foundation pit support are widely used in foundation pit support projects because they simultaneously provide support and water-stopping functions, require less construction space, and are more economical than diaphragm walls. However, during construction, technical defects are inevitable, or the complexity of the site's geological conditions may cause the interlocking piles to fail to act as a water-stopping curtain, resulting in frequent water leakage between the interlocking piles. Another example is the problem of excessive slenderness ratio and stress ratio of steel pipe columns during deep foundation pit excavation. Current technology uses traditional concrete beams for support for safety reasons, but this requires layer-by-layer excavation, brick backfilling, and involves drawbacks such as formwork installation and dismantling, and pre-reserved holes, severely impacting construction efficiency. Yet another example is the construction of steel pipe diagonal bracing at the bottom of the foundation pit, where reaction piers are usually placed on the already poured foundation slab. This makes it difficult to achieve one-time casting of the foundation slab, significantly compromising the overall waterproofing of the slab and the quality of the concrete.

[0004] In view of this, there is an urgent need to invent a high-efficiency support replacement system for deep and large foundation pits that is highly stable, efficient in transfer, easy to install and operate, and has outstanding economic and technical benefits. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide an efficient support replacement system for deep and large foundation pits.

[0006] This efficient support system for deep and large foundation pits includes a foundation pit water-stop curtain, a safety protection passage, steel pipe internal support and steel section internal support. Grouting holes are set on the ground above the leakage point of the foundation pit water-stop curtain, and water pipes are set in the horizontal direction inside the leakage point.

[0007] A safety protection passage is set up at the bottom of the foundation pit. Steel pipe internal supports are installed at the position of the steel waler of the foundation pit. Steel internal supports are installed between the steel pipe concrete columns in the foundation pit. Foundation piles are set at the bottom of the foundation pit. Concrete pile caps are poured on the top of the foundation piles. Steel transition sections are installed on the pile caps. Steel diagonal bracing of the foundation pit is installed on the top of the steel transition sections. A suspended construction platform is installed between the lattice columns in the foundation pit.

[0008] Preferably, the foundation pit water-stop curtain includes cast-in-place piles and plain concrete compaction piles, which are interlocked and connected. Grouting holes are provided on the ground above the leakage points of the pile joints of the cast-in-place piles and plain concrete compaction piles. Water inlet pipes are installed horizontally inside the leakage points of the pile joints of the cast-in-place piles and plain concrete compaction piles. Cement blocks are used to fill the gaps between the water inlet pipes and the foundation pit water-stop curtain. The water inlet pipes are connected upwards to the top of the pit. A water pump is installed at the top of the pit. A drainage ditch is provided on the foundation soil outside the foundation pit. The water pump is used to pump the seepage water in the water inlet pipes into the drainage ditch. Vent holes are provided between adjacent grouting holes.

[0009] Preferably, a water inlet hole is provided at the end of the horizontal section of the water inlet pipe, and a water pipe is provided in the vertical section of the water inlet pipe, which is connected to a water pump.

[0010] As a preferred option, the safety protection passage includes scaffold horizontal bars, scaffold vertical bars, prefabricated steel steps, steel guardrails, and rainproof color steel plates. The ends of the scaffold horizontal bars are anchored to the trench steel waist beams of the foundation pit via connecting fasteners.

[0011] Preferably, auxiliary prestressed suspension ropes are installed at both ends of the steel pipe internal support. Tensioning end plates and flexible joints are set at the ends of the steel pipe internal support. Steel strands are threaded between the tensioning end plates and flexible joints at both ends and prestressed tensioning and locking are applied. The prestressed suspension ropes are respectively sleeved on both ends of the steel pipe internal support and connected to the pre-embedded hooks set on the cast-in-place piles on both sides. The tensioning end plates are provided with steel strand reserved holes at equal intervals in the circumference.

[0012] As a preferred embodiment, the steel internal support is provided with steel clamps at both ends, and the steel clamps are installed on the steel-concrete composite column. The steel clamps at both ends are connected into a whole by a steel support beam in the middle. The surface of the steel-concrete composite column is provided with two sets of upper and lower limiting rings, and the steel clamps are set between the upper and lower sets of limiting rings by connecting bolts.

[0013] As a preferred embodiment, the internal steel support includes a steel clamp, a clamp connection section, and a steel support beam. The steel clamp on one side is provided with a clamp connection section, which is connected and fixed to the steel support beam by anchor bolts through connecting plates on the left and right sides.

[0014] As a preferred option, a circumferential water-stop steel plate is installed in the middle of the steel transition section, a cast-in-place base slab is poured above the pile cap support, some steel transition section segments are embedded in the cast-in-place base slab, and the outer surface of the steel transition section segments embedded in the cast-in-place base slab is covered with waterproof membrane.

[0015] As a preferred option, the suspended construction platform is equipped with hanging plates around the perimeter of the lattice column, and hooks are installed around the top surface of the suspended construction platform. Prestressed lifting ropes are installed between the hooks and the lattice column. The suspended construction platform is used for the pouring of the cast-in-place foundation slab in the foundation pit.

[0016] The beneficial effects of this utility model are:

[0017] 1) This utility model addresses the problem of water seepage in interlocking piles in foundation pits. Based on cement block sealing and secondary grouting, it diverts water from the foundation soil to the water pipe by setting up a horizontal water pipe. By vertically extending the water pipe, atmospheric pressure is used to achieve water pressure balance inside the pipe. A pumping device is also set up to achieve dynamic adjustment, which greatly improves the seepage sealing effect of interlocking piles in foundation pits.

[0018] 2) This utility model uses clamp-type steel internal supports to replace traditional concrete beam supports, which effectively solves the problem of excessive slenderness ratio and stress ratio of steel pipe columns during deep foundation pit excavation, while greatly improving on-site construction efficiency and ensuring the safety of foundation pit support and superstructure.

[0019] 3) This utility model achieves the construction effect of the pile cap reaction seat penetrating the bottom plate without leaving a hole by pre-embedded steel transition section, thereby realizing the one-time casting of the foundation pit bottom plate, effectively improving the overall waterproofness of the bottom plate and the forming quality of the bottom plate concrete. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the interlocking pile leakage sealing structure in this utility model;

[0021] Figure 2 This is a schematic diagram of the water pipe installation in this utility model;

[0022] Figure 3 This is a schematic diagram of the installation of the transverse steel support in this utility model;

[0023] Figure 4 This is a utility model Figure 3 Sectional view of AA in the middle;

[0024] Figure 5 This is a schematic diagram of the permanent and temporary combined steel internal support structure in this utility model;

[0025] Figure 6 This is a utility model Figure 5 Sectional view of AA in the middle;

[0026] Figure 7 This is a front view of the safety protection passage structure for the foundation pit in this utility model;

[0027] Figure 8 This is a side view of the safety protection passage structure for the foundation pit in this utility model;

[0028] Figure 9 This is a schematic diagram of the installation of the suspended construction platform in this utility model;

[0029] Figure 10 This is a schematic diagram of the installation of steel diagonal bracing on the foundation pit bottom plate in this utility model.

[0030] In the diagram: 1-Foundation soil; 2-Plain concrete compaction pile; 3-Cast-in pile; 4-Water pipe; 5-Cement block; 6-Water inlet hole; 7-Grouting hole; 8-Vent hole; 9-Water pump; 10-Water pipe; 11-Drainage ditch; 12-Cap beam; 13-Embedded hook; 14-Prestressed suspension rope; 15-Flexible joint end; 16-Tensioning end plate; 17-Transverse steel support; 18-Steel strand; 19-Anchorage end; 20-Foundation pile; 21-Reserved reinforcement; 22-Steel-concrete composite column; 23-Connecting bolt; 24-Steel clamp. 25-Limiting ring; 26-Connecting plate; 27-Anchor bolt; 28-Clamping connection section; 29-Steel support beam; 30-Prefabricated steel steps; 31-Scaffolding horizontal bar; 32-Scaffolding upright; 33-Steel guardrail; 34-Rainproof color steel plate; 35-Channel steel waist beam; 36-Connecting fastener; 37-Lattice column; 38-Hanging plate; 39-Construction platform; 40-Hook; 41-Steel diagonal brace; 42-Steel transition section; 43-Waterproof steel plate; 44-Cast-in-place base slab; 45-Pile cap support; 46-Waterproof membrane. Detailed Implementation

[0031] The present invention will be further described below with reference to embodiments. The description of the embodiments below is only for the purpose of helping to understand the present invention. It should be noted that, for those skilled in the art, several modifications can be made to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0032] As one example, such as Figure 1 and Figure 2 As shown, this efficient support replacement system for deep and large foundation pits includes a foundation pit water-stop curtain. Grouting holes 7 are installed on the ground above the leakage point of the foundation pit water-stop curtain, and water pipes 4 are installed horizontally inside the leakage point.

[0033] A safety protection passage is set up at the bottom of the foundation pit. Steel pipe internal supports are installed at the position of the steel waler of the foundation pit. Steel internal supports are installed between the steel pipe concrete columns 22 in the foundation pit. Foundation piles 20 are set at the bottom of the foundation pit. Concrete pile cap piers 45 are poured on the top of the foundation piles 20. Steel transition sections 42 are installed on the pile cap piers 45. Steel diagonal braces 41 are installed on the top of the steel transition sections 42. A suspended construction platform 39 is installed between the lattice columns 37 in the foundation pit.

[0034] The foundation pit water-stop curtain includes cast-in-place piles 3 and plain concrete compaction piles 2. The cast-in-place piles 3 and plain concrete compaction piles 2 are interlocked and connected. Grouting holes 7 are set on the ground above the leakage points of the pile joints of the cast-in-place piles 3 and plain concrete compaction piles 2. Water pipes 4 are set horizontally inside the leakage points of the pile joints of the cast-in-place piles 3 and plain concrete compaction piles 2. Cement blocks 5 are filled between the water pipes 4 and the foundation pit water-stop curtain. The pipe opening of the water pipes 4 is connected upward to the top of the pit. A water pump 9 is set on the top of the pit. A drainage ditch 11 is set on the foundation soil 1 outside the foundation pit. The water pump 9 is used to pump the seepage water in the water pipes 4 into the drainage ditch 11. Vent holes are set between adjacent grouting holes 7.

[0035] A water inlet hole 6 is provided at the end of the horizontal section of the water inlet pipe 4, and a water pipe 10 is provided in the vertical section of the water inlet pipe 4. The water pipe 10 is connected to the water pump 9.

[0036] Example 2

[0037] As another embodiment, this second embodiment, based on the first embodiment, proposes a more specific efficient support replacement system for deep and large foundation pits, such as... Figures 3 to 10 As shown: It also includes safety protection passages, steel pipe internal supports and steel section internal supports.

[0038] like Figure 7 and Figure 8 As shown, the safety protection passage includes scaffold horizontal bars 31, scaffold vertical bars 32, prefabricated steel steps 30, steel guardrails 33, and rainproof color steel plates 34. The ends of the scaffold horizontal bars 31 are anchored to the pit channel steel waist beams 35 via connecting fasteners 36.

[0039] like Figure 3 and Figure 4 As shown, auxiliary prestressed suspension ropes 14 are installed at both ends of the steel pipe internal support. Tensioning end plates 16 and flexible joint ends 15 are set at the ends of the steel pipe internal support. Steel strands 18 are threaded between the tensioning end plates 16 and flexible joint ends 15 at both ends and prestressed tensioning and locking are applied. The prestressed suspension ropes 14 are respectively sleeved on both ends of the steel pipe internal support and connected to the pre-embedded hooks 13 set on the cast-in-place piles 3 on both sides. The tensioning end plates 16 are provided with steel strand 18 reserved holes at equal intervals in the circumference.

[0040] like Figure 5 and Figure 6 As shown, the steel internal support is provided with steel clamps 24 at both ends. The steel clamps 24 are installed on the steel pipe concrete column 22, and the two ends of the steel clamps 24 are connected into a whole by the steel support beam 29 in the middle. The surface of the steel pipe concrete column 22 is provided with two sets of upper and lower limiting rings 25, and the steel clamps 24 are set between the upper and lower sets of limiting rings 25 by connecting bolts 23.

[0041] The internal steel support includes a steel clamp 24, a clamp connection section 28, and a steel support beam 29. The steel clamp 24 on one side is provided with a clamp connection section 28. The clamp connection section 28 is connected and fixed to the steel support beam 29 through the left and right connecting plates 26 using anchor bolts 27.

[0042] like Figure 10 As shown, a circumferential water-stop steel plate 43 is provided in the middle of the steel transition section 42, and a cast-in-place base slab 44 is poured above the pile cap support 45. Some sections of the steel transition section 42 are embedded in the cast-in-place base slab 44, and the outer surface of the steel transition section 42 embedded in the cast-in-place base slab 44 is covered with a waterproof membrane 46.

[0043] like Figure 9 As shown, the suspended construction platform 39 is equipped with hanging plates 38 that are hung on the lattice column 37 around its perimeter. The top surface of the suspended construction platform is equipped with hooks 40 around its perimeter. Prestressed suspension ropes 14 are installed between the hooks 40 and the lattice column 37. The suspended construction platform 39 is used for the pouring construction of the cast-in-place base slab 44 in the foundation pit.

[0044] It should be noted that the parts in this embodiment that are the same as or similar to those in Embodiment 1 can be referred to each other, and will not be repeated in this application.

[0045] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

Claims

1. A high-efficiency support replacement system for deep and large foundation pits, characterized in that, This includes a foundation pit water-stop curtain, a safety protection passage, steel pipe internal support and steel section internal support. Grouting holes are set on the ground above the water leakage point of the foundation pit water-stop curtain, and water pipes are set in the horizontal direction inside the water leakage point. A safety protection passage is set up at the bottom of the foundation pit. Steel pipe internal supports are installed at the position of the steel waler of the foundation pit. Steel internal supports are installed between the steel pipe concrete columns in the foundation pit. Foundation piles are set at the bottom of the foundation pit. Concrete pile caps are poured on the top of the foundation piles. Steel transition sections are installed on the pile caps. Steel diagonal bracing of the foundation pit is installed on the top of the steel transition sections. A suspended construction platform is installed between the lattice columns in the foundation pit.

2. The high-efficiency support replacement system for deep and large foundation pits according to claim 1, characterized in that, The foundation pit cutoff wall includes cast-in-place piles and plain concrete compaction piles, which are interlocked. Grouting holes are installed on the ground above the leakage points of the pile joints of the cast-in-place piles and plain concrete compaction piles. Water inlet pipes are installed horizontally inside the leakage points of the pile joints of the cast-in-place piles and plain concrete compaction piles. The gaps between the water inlet pipes and the foundation pit cutoff wall are filled with cement stones. The water inlet pipes are connected upwards to the top of the pit, where a water pump is installed. A drainage ditch is provided on the foundation soil outside the foundation pit. The water pump is used to pump the seepage water in the water inlet pipes into the drainage ditch. Vent holes are installed between adjacent grouting holes.

3. The high-efficiency support replacement system for deep and large foundation pits according to claim 2, characterized in that, A water inlet hole is provided at the end of the horizontal section of the water inlet pipe, and a water pipe is installed in the vertical section of the water inlet pipe, which is connected to the water pump.

4. The high-efficiency support replacement system for deep and large foundation pits according to claim 1, characterized in that, The safety protection passage includes scaffold horizontal bars, scaffold vertical bars, prefabricated steel steps, steel guardrails, and rainproof color steel plates. The ends of the scaffold horizontal bars are anchored to the trench steel waist beams of the foundation pit via connecting fasteners.

5. The high-efficiency support replacement system for deep and large foundation pits according to claim 1, characterized in that, Auxiliary prestressed suspension ropes are installed at both ends of the steel pipe internal support. Tensioning end plates and flexible joints are set at the ends of the steel pipe internal support. Steel strands are threaded between the tensioning end plates and flexible joints at both ends and prestressed tensioning and locking are applied. The prestressed suspension ropes are respectively sleeved on both ends of the steel pipe internal support and connected to the pre-embedded hooks set on the cast-in-place piles on both sides. Steel strand reserved holes are set at equal intervals around the tensioning end plates.

6. The high-efficiency support replacement system for deep and large foundation pits according to claim 1, characterized in that, The steel internal support is equipped with steel clamps at both ends, which are installed on the steel-concrete composite column. The steel clamps at both ends are connected into a whole by a steel support beam in the middle. The surface of the steel-concrete composite column is provided with two sets of upper and lower limiting rings, and the steel clamps are set between the upper and lower sets of limiting rings by connecting bolts.

7. The high-efficiency support replacement system for deep and large foundation pits according to claim 1, characterized in that, The internal steel support includes steel clamps, clamp connection sections, and steel support beams. A clamp connection section is provided on one side of the steel clamp, and the clamp connection section is connected and fixed to the steel support beam by anchor bolts through the connecting plates on the left and right sides.

8. The high-efficiency support replacement system for deep and large foundation pits according to claim 1, characterized in that, A circumferential water-stop steel plate is installed in the middle of the steel transition section. A cast-in-place base slab is poured above the pile cap support. Some steel transition section segments are embedded in the cast-in-place base slab. The outer surface of the steel transition section segments embedded in the cast-in-place base slab is covered with waterproof membrane.

9. The high-efficiency support replacement system for deep and large foundation pits according to claim 1, characterized in that, The suspended construction platform is equipped with hanging plates around the lattice columns, and hooks are installed around the top surface of the suspended construction platform. Prestressed ropes are installed between the hooks and the lattice columns. The suspended construction platform is used for the pouring of cast-in-place foundation slabs in the foundation pit.

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